PITTSBURGH -- Last week, friends and family gathered together at the Unity Baptist Church in Braddock to remember a man whose cause of death is still a mystery.

During a preliminary investigation, the Allegheny County medical examiner said suburban Pittsburgh police did not use excessive force against a man who died after officers subdued him with a Taser.

Dr. Karl Williams said there was no evidence that excessive force was used against Andre Thomas, 37.

Williams didn't characterize what excessive force meant or disclose autopsy findings.

Thomas died early Tuesday after Swissvale police arrested him. His father and witnesses said an officer stomped on Thomas after he'd been stunned three times.

Police said Thomas was acting erratically and trying to enter people's homes on Hawthorne Avenue shortly before midnight Monday. Police said the Taser was used after Thomas made "furtive movements" toward officers.

Thursday afternoon, District Attorney Stephen Zappala outlined the timeline of events.

While some witnesses have said police punched and kicked Thomas, Zappala said there's no evidence to indicate that.

"No trauma to him of which is consistent with a violent beating they describe," he said.

At 11 p.m. the night of the incident, a friend of Thomas' said he picked him up in Braddock. The friend told investigators Thomas was acting irrational, claiming someone was trying to kill him.

In Swissvale, the friend said Thomas exited the vehicle and took off, according to Zappala.

At 11:45 p.m., the first of eight 911 calls from residents in Swissvale was taken, with residents complaining a man was pounding on their doors asking for help.

At 11:50 p.m., three Swissvale police officers encountered Thomas. He allegedly told them men were behind a home trying to shoot him.

Two of the officers went to check it out and a third remained with Thomas, ordering him to the ground, Zappala said.

"He's very irrational, and he's very difficult to deal with, and they conclude he's a danger to himself," said Zappala.

At 11:51 p.m., as Thomas attempted to flee, an officer used a Taser to subdue him. Police then hit Thomas with a Taser two more times before handcuffing him.

Between 11:55 p.m. and 11:57 p.m., emergency personnel arrived, Zappala said.

"His breathing, he has a good pulse, but he cannot coherently converse," Zappala said. "His pupils are restrictive but not reactive, indicating he may have drugs in his system."

Zappala said Thomas then vomited, and his pulse began to weaken before he went into cardiac arrest shortly after midnight.

"I thought it was important that we tell people what happened and that we take this very seriously," Zappala said.

While Zappala said it's too early to draw any conclusions, he did address the possibility of excited delirium, which is a condition where a person becomes irrational. The body temperature rises and organs fail and often times, it's associated with drug use.

Doctors and law enforcement officers don't all agree on whether the condition of excited delirium exists, but it is a term more medical examiners are using to explain why people die suddenly in police custody.

Zappala said Allegheny County police as well as the FBI are conducting investigations into the death.

Thursday afternoon, Thomas' family hired an attorney to investigate the death.