The targeted killing of Iranian nuclear scientists through military actions by the U.S. and Israel has sparked concern over the potential destabilization of the Iranian regime. This instability could lead to a weakened grip on uranium stockpiles and the dissemination of nuclear expertise, heightening the risk of nuclear proliferation.

Experts indicate that although Iran may find replacements for the personnel it has lost, the expertise these individuals possessed is not as easily restored. Additionally, undisclosed facilities within Iran may render sensitive materials and knowledge susceptible to exploitation.

“At present, the threat of nuclear terrorism or the diversion of nuclear materials to the black market is minimal,” stated Kelsey Davenport, who serves as the director of nonproliferation policy at the Arms Control Association.

“Non-state actors would encounter significant obstacles in acquiring enriched uranium, and it is improbable that they possess the necessary infrastructure to further enrich it to weapons-grade levels and convert it into the metallic form needed for the core of a warhead,” she explained.

Mourners in Tehran gathered around the flag-covered coffins of Iranian generals, nuclear scientists, and their family members, who fell victim to the Israeli strikes on June 28, 2025. (Vahid Salemi/AP)

“However, if the current Iranian government implodes or the conflict causes significant internal instability, there is an increased risk that nuclear materials will be stolen or diverted to undeclared sites.”

“There is also a risk that Iranian nuclear scientists may be willing to sell their expertise to states or non-state actors seeking nuclear weapons,” Davenport said in a new report.

Several senior figures in Iran’s nuclear and defense infrastructure have been killed over the past two years, coinciding with the campaign of U.S. and Israeli strikes on Iran’s nuclear facilities between 2025 and 2026.

Among them is Hossein Jabal Amelian, head of the Organization of Defensive Innovation and Research (SPND), who was killed in 2026 during Operation Rising Lion and Operation Epic Fury.

President Pezeshkian said Iran would rebuild the nuclear facilities targeted by the U.S., and make them stronger in 2025. (Iranian Presidency/Handout/Anadolu via Getty Images)

SPND is seen as the successor to Iran’s pre-2004 nuclear weapons program and plays a key role in new weaponization research.

Others killed in 2025 include Mohammad Mehdi Tehranchi, Akbar Motallebizadeh and Said Borji, all linked to weaponization work.

“The full impact of this campaign on Iran’s weaponization capabilities remains unclear,” Jim Lamson, a senior research associate at the Center for Nonproliferation Studies, told Fox News Digital.

“There will be replacements of the managers and scientists, but the impact on the killed officials’ experience and expertise will be hard to replace,” the former CIA analyst said.

“Many key scientists involved in suspected weaponization work were killed in 2025 and 2026.”

“Their successors may also fear being targeted in the future, whether by military strikes or assassination. That could affect their motivation and willingness to participate in any nuclear weapons program.”

Mourners carry the coffin of Iranian nuclear scientist Mohammad Reza Sedighi Saber. (Alborz Irani/SOPA Images/LightRocket via Getty Images)

Lamson also said many of those targeted were embedded in sensitive areas of Iran’s nuclear work, including the fuel cycle and weaponization.

“These scientists had expertise in areas of the nuclear fuel cycle of key concern for nuclear weapons, including the production of highly enriched uranium (HEU), which was Iran’s main pathway for fissile material,” he said.

“The scientists also had expertise in weaponization — that is, in key aspects of the design and production of nuclear explosive devices,” Lamson added.

That said, U.S. and Israeli targeted strikes have also hit a network of sites tied to their work, creating extra obstacles for Iran’s program in the near term, he said.

“We have identified at least 11 weaponization-related sites that have been hit since 2024,” Lamson said.

“These include SPND headquarters, a newly identified site called Min-Zadayi in northeast Tehran, SPND’s Taleghan and Sanjarian explosives testing sites, the Defense Ministry’s Shahid Meisami complex in western Tehran and several research universities.”

These facilities were all involved in neutronics, explosives, metallurgy and nuclear physics — all tied to nuclear weapons development, he said.

Satellite imagery shows reinforcement efforts at Pickaxe Mountain site as Trump says Tehran is pursuing nuclear weapons. (Vantor/Reuters)

Despite the scale of the latest strikes, Iran retains enriched nuclear material, with President Donald Trump saying April 17 that the U.S. would work with Iran to recover “nuclear dust” — enriched uranium — from sites, adding that both countries would use heavy machinery to remove it.

The International Atomic Energy Agency also estimates Iran still holds more than 200 kilograms of uranium enriched to 60% at Esfahan—enough for roughly five weapons if further enriched.

Iranian Foreign Minister Seyed Abbas Araghchi also said it remains “under the rubble” of previous strikes and that Tehran has no plans to recover it.

“It is always possible that Iran has additional sites that were not known to Israel and the U.S.,” Lamson said.

“We will have to wait to see how much these operations translate into a lasting strategic impact on Iran’s ability to produce nuclear weapons.”

“It’s easier to identify the damage and death caused by the Israeli and U.S. strikes, and harder to assess their actual impact on Iran’s capabilities and intentions to produce a nuclear weapon,” Lamson clarified.

The WWE universe was taken by surprise when legendary wrestler Brock Lesnar seemingly bid farewell to his illustrious career at WrestleMania 42 on Sunday night. The dramatic turn of events unfolded at Allegiant Stadium, where Lesnar faced a swift defeat against his adversary, Oba Femi, in a mere four minutes and 42 seconds.

In a poignant moment that left fans and peers alike stunned, Lesnar placed his gloves and boots in the center of the ring, hinting at his retirement from the sport. His emotional gesture was followed by a heartfelt embrace with Paul Heyman, his longtime friend and onscreen ally, before Lesnar turned to give a final wave to the crowd.

The atmosphere inside the stadium was charged with emotion, as Netflix’s broadcast captured the audience’s overwhelming response. Chants of “Thank you, Lesnar” echoed through the arena, honoring the 48-year-old’s contributions to the wrestling world as he departed the ring one last time.

Beyond his WWE achievements, Lesnar’s career highlights include a tenure as a heavyweight UFC fighter. He retires as a ten-time WWE champion and a two-time Royal Rumble victor, solidifying his status as a true legend in the wrestling realm.

Lesnar, who also had a stint as a heavyweight UFC fighter, walks away from the sport as a 10-time WWE champion, a two-time Royal Rumble winner and bona fide legend.

It didn’t take long for tributes to pour in for the 48-year-old, with Kurt Angle writing on X: ‘Love you my brother. There will only be one like you. Enjoy retirement Brock.’ 

WWE legend Brock Lesnar appeared to retire from the sport at WrestleMania 42 on Sunday

The 48-year-old was overcome with emotion as he waved goodbye to fans in Las Vegas

Lesnar had an emotional embrace with on-screen manager Paul Heyman at Allegiant Stadium

Lesnar began life with the WWE back in 2002, following a successful college wrestling career that saw him a two-time NJCAA All-American and accrue a staggering 106-5 record over four years.

After signing with the wrestling promotion, Lesnar worked his way into the main roster and eventually became one of the biggest stars in the organization.

However, his first stint in the WWE would come to an end in 2004. Following a defeat at WrestleMania XX, he cited burnout, injuries and creative dissatisfaction as his reasons for walking away. 

Lesnar would later return to the promotion in 2012 and earned a number of WWE championship titles before seemingly retiring at WrestleMania 36. 

That decision, however, was short-lived and he returned to the ring in 2021 rocking a new ‘cowboy’ look that featured a beard and ponytail.

In 2023, Lesnar was named in a bombshell sex trafficking lawsuit against WWE co-founder Vince McMahon, filed by his former employee Janel Grant. 

As a result of the lawsuit, Lesnar was removed from the WWE’s roster and wiped from their event plans. He would endure a two-year exile from the organization.

He returned at Summer Slam in August 2025, despite the Grant lawsuit remaining active at the time. He took part in a handful of fights between then and Sunday night, before officially retiring from the sport.

Lesnar’s final WWE match saw him get defeated to Oba Femi in less than five minutes

The WWE icon bid farewell in-front of a packed out Allegiant Stadium in Las Vegas

Lesnar also had a successful career in the UFC during a hiatus from his wrestling endeavors

Though he’s best-known for his time in the squared circle, Lesnar also found success away from wrestling. After leaving WWE for the first time in 2004, he attempted to embark on a professional football career. 

Lesnar participated in the NFL Scouting Combine at the time but later suffered a broken jaw and hand from a motorcycle accident which put his progress on hold. 

Despite the injuries, a number of NFL teams still held an interest in Lesnar and, in July 2004, he signed with the Minnesota Vikings as a defensive tackle. However, his time with the franchise was short-lived and he was eventually released in August. 

After his dreams of being on the gridiron came crashing down, Lesnar then decided to try his hand – literally – at mixed martial arts.

He began fighting for a promotion known as ‘K-1’, in April 2006, and won his first bout via submission in the first round – bring global attention to his MMA skills. 

He would eventually sign with Dana White’s UFC in 2008, which proved to be a massive success for the organization given Lesnar’s national star power. 

Despite losing his first fight, UFC chief White stuck by Lesnar and offered him a multi-fight deal. Again, this proved to a wise call as Lesnar would later become the UFC heavyweight champion following a win over Randy Couture in November 2008.

In total, he had eight UFC fights, winning four of them and losing three – with the final bout being ruled as a no-contest after he tested positive for clomiphene.