GLENDALE, Ariz. () Federal officials are investigating “several threats of unknown credibility” toward expected attendees at Sunday’s memorial to slain conservative activist Charlie Kirk, two law enforcement sources have confirmed to .

Threats against President Donald Trump, Vice President JD Vance and members of the Kirk family are among those being looked into, the sources said. The information regarding the threats was contained in a law enforcement memo issued by several federal agencies, including the FBI, the Department of Homeland Security and the Secret Service.

The sources confirmed there have not been any verified, credible threats made against the event, but rather threats of unknown credibility, which are not verified but still must be thoroughly investigated.

The FBI and Secret Service did not offer any official comment on the assessment or the threats.

“I know Director Curran and Secretary Noem are all over there, so there is going to be national and world leaders at this event, so we are very much focused on the security and safety of this event,” DHS spokeswoman Tricia McLaughlin told on Friday.

According to the law enforcement memo, as first reported by ABC, “Violent extremists and unaffiliated lone offenders may view the memorial service or related events as attractive attack targets due to the attendance of these individuals, other senior US government officials, state and local government officials, and political activists and due to major international media attention.”

Charlie Kirk’s funeral to have Super Bowl-level security

The DHS has designated Sunday’s event as a Special Event Assessment Rating, or SEAR, Level 1 event, a DHS official told , meaning it will carry the same level of security as the Super Bowl.

Police found a suspicious bag Wednesday at Turning Point USA headquarters in Phoenix, Fox News reported. A bomb squad was called in to investigate, and the bag was deemed safe.

Sunday’s funeral service will be held at State Farm Stadium in nearby Glendale, Arizona. Turning Point’s program note states that bags will not be allowed into the stadium, and enhanced security measures will be in place, which may result in longer wait times for attendees.

Secret Service told that teams were on the ground in Phoenix and Glendale, working alongside state, local and federal partners.

State Farm Stadium holds more than 60,000 people, and an indoor overflow room has been set up in case the event reaches capacity.

Who will speak at Charlie Kirk’s funeral?

At Sunday’s service, Trump and Vance are scheduled to deliver remarks alongside Kirk’s widow, Erika, who was unanimously elected as the new CEO and board chair of Turning Point USA following her husband’s death. 

Other expected attendees include White House chief of staff Susie Wiles, Secretary of State Marco Rubio, Health Secretary Robert F. Kennedy Jr., Defense Secretary Pete Hegseth and Director of National Intelligence Tulsi Gabbard.

Donald Trump Jr., Tucker Carlson, Stephen Miller and Sergio Gor are also among the scheduled speakers.

What happened to Charlie Kirk?

Kirk, 31, was shot in the neck last week while speaking at a campus courtyard event at Utah Valley University. He was widely credited with energizing young Republican voters and playing a key role in Trump’s 2024 presidential victory.

Kirk grew up in Illinois, but spent much of his adult life in Scottsdale, Arizona. He was an evangelical Christian and often quoted the Bible during his talks and debates. He was outspoken about his criticism of diversity, equity and inclusion programs, abortion and same-sex marriage.

‘s Damita Menezes and Alex Caprariello contributed to this report.