Updated at 5:10 p.m. ET: Former Commerce Secretary John Bryson will not face criminal charges in California after a trio of traffic accidents last month, according to the Los Angeles County district attorney’s office.

The announcement came after prosecutors reviewed evidence presented by San Gabriel police, said spokeswoman Sandi Gibbons.

Bryson, 68, resigned June 21, 10 days after saying he would take a leave of absence to focus on his health issues. He said the crashes were caused by seizures and he didn't want his health to distract from his job.

Authorities said Bryson, on June 9, struck a Buick stopped for a train, spoke to its three occupants, hit it again as he drove away, and then rammed into another vehicle with his Lexus a few minutes later in a nearby Rosemead, the Los Angeles Times reported. The men in the Buick followed Bryson and called 911, police said. 

Bryson was found unconscious in his vehicle, and was cited for felony hit-and run.

The district attorney’s report released Tuesday said Bryson’s blood tested negative for alcohol and controlled substances but positive for Ambien at “low end therapeutic levels.”

“Criminalists can not say it was a factor in driving or the collisions," the report said.

Doctors treating Bryson agreed he was “suffering from confusion following a seizure and crashed as a result,” it said.

Doctors said there was insufficient evidence to show “knowing failure to provide personal information for hit and run” or to prove driving under the influence, the report said.

Manuel Balce Ceneta / AP file

Former Secretary of Commerce John Bryson

Bryson's neurologist initially diagnosed Bryson as having a "complex partial seizure," a Commerce Department official said earlier. Bryson had a "limited recall of the events" surrounding the seizure, which was said to be Bryson's first, a Commerce official said.

Bryson had been in California to deliver the commencement address June 7 at Pasadena Polytechnic School where his four children had attended, the Times reported.

Bryson, who has a home in San Marino, is the former head of Edison International, the holding company that owns Southern California Edison, and has served on boards of major corporations, including the Boeing Co. and the Walt Disney Co.

This article incudes reporting by The Associated Press and msnbc.com's Jim Gold. Follow him on Facebook here.

More content from msnbc.com and NBC News:

• Independence Day irony: PTSD has many vets dreading, avoiding fireworks
• Storms, dangerous heat to continue into July 4, and beyond
• Kansas City cop accused of sex with women in exchange for no arrest
• Motorcyclist killed on way to memorial for another biker who died in crash
• Video: Dual-engine failure caused jet crash

Follow US News on msnbc.com on Twitter and Facebook