Postal inspectors are investigating the incident as a “potentially intentional act,” said U.S. Postal Inspector Michael Martel. There was no information about a possible motive. Nearly 2 million people live in the metropolitan area of San Jose, about 50 miles south of downtown San Francisco.

The fire happened just before 3 a.m. on the 6500 block of Crown Boulevard. According to the San Jose Fire Department, a vehicle crashed into the post office and caught fire. The suspect arrested was identified as 44-year-old Richard Tillman, Pat's brother, according to U.S. Postal Inspector Matthew Norfleet.

Richard Tillman, who is the brother of former NFL player Pat Tillman, is accused of driving a vehicle into a post office.