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 has been charged with attempted murder following a stabbing incident that took place on July 19 at an apartment complex on Newport Terrace in Deerfield Beach. Officers responded at approximately 11:30 a.m. to a report of a stabbing. Upon arrival, they discovered the victim with a stab wound to the upper left chest, according to a probable cause arrest affidavit. Vargas Arana was present at the scene and exhibited a bump on his head and a cut on his left wrist.

The victim, who was already on oxygen due to COPD, was quickly transported to the hospital by paramedics. Medical staff determined the knife had punctured his lung and resulted in internal bleeding. He was last reported to be in stable condition.

Investigators found out that the victim was returning home after shopping and having lunch. His wife received him outside the apartment, and they started walking inside together. Suddenly, Vargas Arana, a neighbor they recognized, allegedly ran down the stairs wearing surgical gloves and holding a knife with a black handle and welded blades, the affidavit noted. The suspect is accused of stabbing 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.