A teenager who was shot multiple times in the head and had a sheet placed over him by paramedics — who realized minutes later that he was still breathing — has died.

Erin Carey, 17, of the Austin neighborhood was pronounced dead at 1:14 a.m. Tuesday at Stroger Hospital.

He was shot about 4:45 a.m. Monday in the 1300 block of South Loomis outside the ABLA/Brooks Homes, a CTA housing facility, in the University Village neighborhood. Four others were also shot — one of them fatally.

Authorities are trying to determine how paramedics mistakenly thought Carey was dead. On Tuesday, CFD spokesman Larry Langford said officials were investigating why Carey wasn’t treated in “a more timely manner.”

“We are reviewing dispatch recordings, phone calls and our paramedics to determine what did led to the patient being left under a sheet when he had not been pronounced dead, and in fact had life signs despite a traumatic wound from which he could not recover,” Langford said.

At a Monday news conference, CPD Deputy Supt. Anthony Riccio said he didn’t know “the length of time [he was under the sheet] but from what my understanding of the incident is — that individual has a catastrophic injury.”

WLS-TV (Channel 7) recorded video of the teen moving under the sheet and reported he was covered for several minutes before a paramedic uncovered him and began performing chest compressions.

“He was shot in the head and the prognosis is not good. I do understand that paramedics looked at him, believed him to be deceased, covered him with that sheet and moved on to another individual who was nearby who was also shot,” Riccio said.

“(Officers) saw a motion, movement, underneath the sheet. Officers who were present notified the paramedics ‘this man is still alive’ and treatment began on him as well,” Riccio said.

“Again, his injuries are catastrophic, that is something I think definitely has to be looked at to find out exactly what happened,” Riccio said. “He’s on full life support. … I understand the family is there with him and they’ll have to make a decision on how to proceed.”

Chicago Fire Department Commissioner Jose Santiago said Monday after an unrelated news conference that he was unaware of specifics and couldn’t immediately comment.

“We’re looking into it right now,” he said, briefly noting that paramedics consider several factors when assessing gunshot victims.

“There’s also something going on that a lot of people forget, it’s known as triage,” Santiago said, referring to the practice of first responders sorting victims by medical priority in order to increase the number of survivors.

“When the first ambulance gets on the scene they’ll take a look at the victims and they will concentrate on the ones they know they can save, right away. That’s the first thing that takes place,” Santiago said.

Riccio said multiple shell casings found at the scene suggest an exchange of gunfire from multiple shooters.

A woman in her early 20s, shot multiple times in her head and arm, was pronounced dead at the scene.

A 21-year-old man was shot in his leg, a 23-year-old man was shot in his arm and another 23-year-old man was shot multiple times in his abdomen.

The shooting stemmed from an argument at a party, police said.

“At least four of the victims are known to the Chicago police department,” Riccio said, adding that there is an ongoing gang conflict in that area.

“We’re working to find out why exactly these individuals were targeted and what caused the shooting … at this time none of the non-fatal victims are cooperating with the police,” he said.

The shooting occurred adjacent to the CTA housing facility and about a block west of the Chicago Police Department’s 12th district police station, also known as the Near West District.

The shooting also occurred about right outside the front entrance of the Jane Addams Family Resource Center, less than a block from Urban Prep Academy’s West Campus and three blocks south of Taylor Street — the main drag of Little Italy.

Contributing: Sun-Times Wire