BRISTOL, Conn. — Boston police have been investigating whether jailed former New England Patriot Aaron Hernandez may have been the gunman in a 2012 double slaying, according to a search warrant request released Thursday.

Hernandez, who is awaiting trial on murder charges in a 2013 shooting near his home, was seen on surveillance footage in the same nightclub as the victims the night of the attack in Boston’s South End, authorities have said. But the newly released documents confirm for the first time that police suspect Hernandez could have pulled the trigger.

A lawyer for Hernandez did not immediately respond to a request for comment.

No charges have been filed in the deaths of Daniel Jorge Correia de Abreu and Safiro Teixeira Furtado, who were killed on July 16, 2012, when somebody inside an SUV opened fire on their car. A third person was shot but survived.

In the affidavit and search warrant application released by Superior Court in Bristol, Conn., police write that there is probable cause to believe that Hernandez was driving the vehicle used in the shooting and “may have been the shooter.”

The affidavit was filed on June 28 as police sought to search an SUV they say was involved in the shooting and was found that month at Hernandez’s uncle’s home in Bristol, his hometown. The SUV had been given to Hernandez by a Rhode Island company in exchange for participating in promotional activities, according to court filings.

The SUV was covered in dust and cobwebs and had a dead battery, leading police to believe it has remained untouched in the garage for close to a year, according to the court document.

It is not clear from the affidavit why police believe Hernandez may have pulled the trigger in the 2012 shooting. The section of the affidavit that appears to explain that reason is one of several redacted from the public copy of the document.

Survivor Aquilino Freire told police an SUV pulled up next to them while they were stopped at a traffic light, and he saw someone in the SUV’s back seat laughing, according to the affidavit. Then, several gunshots were fired from the rear passenger seat into the car, Freire told police. Two other people in the car ran away, Freire said.

Authorities found the silver Toyota 4Runner while investigating the slaying of Odin Lloyd, a semi-professional football player whose body was found June 17 near Hernandez’s North Attleborough, Mass., home. Hernandez has pleaded not guilty to murder in that case.

According to the affidavit released Thursday and a second warrant request released earlier this month, police began investigating a possible link between the 2012 and 2013 shootings after receiving an anonymous call on June 22.

The caller was identified in the court documents as Sharif Hasheem, a security supervisor at a Boston nightclub. He told authorities the two shootings were related and that “someone accidentally spilled the beans in front of me.”

The search warrant application also includes a request to search a bag of clothing, identified as belonging to Hernandez, found in the Bristol home. It says police were looking for “clothing and accessories that Aaron Hernandez wore on the night of June 16, 2012.”