Paul Anthony Vargas Arana (Broward County Jail).

A Florida man stabbed his neighbor, who is on oxygen, in an unprovoked attack in the middle of the day, according to authorities.

Paul Anthony Vargas Arana stands accused of attempted murder in a stabbing that occurred on July 19 at an apartment complex on Newport Terrace in Deerfield Beach. Cops responded around 11:30 a.m. for a report of a stabbing. When they arrived, they found the victim suffering from a stab wound to the upper left chest, a probable cause arrest affidavit said. Vargas Arana was also at the scene and was observed with a bump on his head and a cut to his left wrist.

Paramedics rushed the victim, who was already on oxygen because of his COPD, to the hospital. Doctors discovered the knife had punctured his lung and caused internal bleeding. He was last listed in stable condition.

Detectives learned the victim was returning home from shopping and lunch. His wife greeted him outside the apartment and they began to walk inside together. Suddenly, a neighbor they knew, Vargas Arana, came running down the stairs wearing surgical gloves and armed with a black handled knife with blades welded onto it, the affidavit said. The suspect allegedly stabbed the victim “without provocation.”

The victim began fighting back while saying, “Paulie, why are you doing this?” cops wrote. Meanwhile, the victim’s wife ran inside and grabbed a metal pipe, police said. She came back out and hit Vargas Arana in the head with the pipe, according to the affidavit. Deputies arrived and pulled Vargas Arana off the victim.

It’s unknown why Vargas Arana allegedly attacked him. The two have known each other for 10 years. Neighbors opined that Vargas Arana may have been suffering mental health issues.

Cops arrested Vargas Arana and took him to the Broward County Jail, where he’s being held without bond.