Law enforcement officials have said they found evidence of Mr. Conditt’s potential future targets, a mix of addresses and other locations that appeared to have no common thread to link them. Investigators were continuing on Monday to sort through his computer hard drives and other evidence.

Before Mr. Conditt died, a federal criminal complaint was filed against him, charging him with unlawful possession and transfer of a destructive device, and a warrant was issued for his arrest. A federal magistrate judge in Austin sealed an affidavit by investigators that would be expected to summarize their reasons for charging Mr. Conditt. It was unclear when that affidavit would be unsealed.

Investigators have said that Mr. Conditt used his cellphone to record a video in his vehicle after a confrontation with the police in Round Rock, a suburb near Pflugerville. A short time later he detonated one of his bombs inside the vehicle, killing himself. The cellphone survived the explosion.

Mr. McCaul, whose district includes parts of Austin and Pflugerville, apparently has seen the video. He described it on Fox News as a visually dark 25-minute confession. “He said, ‘I wish I was sorry, but I’m not,’ ” Mr. McCaul said. “He refers to himself as a psychopath. ‘I’ve been a sociopath all my life.’ And then even more chilling at the end, he says that ‘maybe I should just blow myself up at a McDonald’s and end the whole thing.’ That’s where he was headed.”

The authorities said Mr. Conditt placed four fairly sophisticated homemade bombs in Austin, hidden in packages left on doorsteps or, in one case, placed with a tripwire along a sidewalk.

In total, one of the worst serial bombers in America in decades killed two men; wounded four other people, including a 75-year-old woman; and terrified residents in the Austin and San Antonio regions. In one 24-hour period, the Austin police responded to 420 suspicious-package calls, all false alarms.

Hundreds of local, state and federal agents and officers were hunting the serial bomber for days. The state deployed a Pilatus high-altitude surveillance airplane equipped with a thermal imaging system. Mr. Conditt was tracked to a hotel parking lot in Round Rock, and when he drove away in his red Nissan Pathfinder, the police followed him and confronted him; the chase ended in a ditch off Interstate 35, where one Austin SWAT officer fired his weapon and Mr. Conditt set off his bomb.

A justice of the peace in Williamson County, Dain Johnson, said on Monday that Mr. Conditt died by his own hand. “There is no final report yet, but the cause of death is suicide,” Judge Johnson said. “He had multiple shrapnel injuries from the bomb.”