FALL RIVER — Authorities Monday identified the man who became unresponsive while swimming at Swansea Town Beach Sunday night and was pronounced dead a short time later as 39-year-old Fall River man Jason Davis.

Davis’ girlfriend told police the couple went to the beach to cool off from the day’s excessive heat, Bristol County District Attorney Thomas Quinn's office said.

She told police she briefly went underwater and after resurfacing saw Davis floating face down, according to DA spokesman Gregg Miliote.

Miliote said Davis suffered from preexisting medical conditions which the Office of the Medical Examiner will take into account when determining the official cause of death.

“It’s not 100 percent clear it was definitely a drowning," Miliote said. "It may have been a medical incident. He did suffer from some medical problems as well."

Davis' girlfriend called for help and, with assistance from three bystanders, pulled Davis out of the water. Miliote said someone performed CPR while waiting for an ambulance to arrive.

According to a Sunday news release from the Swansea Police Department, patrol officers continued CPR until Swansea Ambulance paramedics arrived about 6:15 p.m. and provided advanced life support.

Davis was rushed to Charlton Memorial Hospital, where he was pronounced dead about 7 p.m., according to Miliote.

Lifeguards are on duty at Swansea Town Beach between 10 a.m to 4 p.m., Monday through Sunday, according to the town website.

Swansea Police Lt. Marc Haslam confirmed Davis became unresponsive at the beach during the evening hours when there were no lifeguards on duty.

Email Amanda Burke at aburke@heraldnews.com.