Orlando nightclub killer Omar Mateen was shot at least eight times by police, according to an autopsy report released by the medical examiner in Orange County, Fla.

Mateen's attack on the Pulse nightclub left 49 people dead, and he was killed by law enforcement officers after an hours-long standoff.

"In consideration of the circumstances surrounding the death, and after examination of the body and toxicology analysis, it is my opinion that the death of Omar Mir Seddique Mateen, a 29-year-old white male, shot by law enforcement, is the result of multiple gunshot wounds," the report by Chief Medical Examiner Joshua Stephany reads.

As NPR's Martin Kaste tells our Newscast unit, "his autopsy showed no sign of illegal drugs or alcohol in his system — but there was a slightly higher-than-normal level of a substance associated with a dietary substance for body-building."

The autopsy report says Mateen had blunt force injuries to his torso, without specifying how he sustained them.

The medical examiner also released autopsies for 31 of the shooting victims.

"Most of Mateen's victims were also shot multiple times, but the autopsies did not determine whether any of them were mistakenly shot by police," Martin reports. "Other victims appear to have had more survivable wounds, and they may have died from a loss of blood."

He adds: "There's been some criticism of the Orlando police for taking three hours to make their final assault — something the Justice Department is now reviewing."

As we have reported, Mateen was born in New York City and had previously undergone three interviews by the FBI — "one regarding inflammatory comments to co-workers and another regarding possible links to Moner Mohammad Abu Salha, a U.S. citizen who blew himself up in Syria." Both investigations were closed.

Copyright 2016 NPR. To see more, visit http://www.npr.org/.