After dropping his weapon, Van Tassel asked for a Barack Obama campaign sign, which authorities delivered to him using a bomb squad robot, police said. The man attached the sign and the flag to the overpass and later walked backward to officers, who took him into custody.
No shots were fired and police said the man's gun turned out to be unloaded.
Van Tassel, an Iraq veteran from Santa Barbara, was taken into custody without incident, said police Sgt. Lorenzo Duarte. The sergeant said Van Tassel had been in the Army but he did not have any details of his Iraq service.
As for the man's motive, Duarte said, "The reason appears to be anti-war, but I don't know the specifics."
Police were continuing to investigate a duffel bag and the man's car at the scene but "we have no credible threats or any threats of explosives," police Sgt. Jim Pfleging said.
Pfleging said Van Tassel will receive a mental health evaluation. Telephone directory assistance had no listing for Van Tassel.
Van Tassel was booked for investigation of possession of a concealed firearm, possession of an illegal weapon, conspiracy, resisting arrest, brandishing a weapon, disturbing the peace, wearing a mask for the purpose of committing a crime and allowing an unlicensed driver to drive.
Police investigating the standoff also alleged that Van Tassel carried a weapon into a local radio station last week. He was booked for investigation of burglary, brandishing a weapon and possession of a concealed weapon in connection with that incident.
Police also arrested a second man, Aaron Levy, 33. Investigators allege Levy drove Van Tassel to the scene Monday and "was aware of what was going to happen," Duarte said.
Levy was booked for investigation of conspiracy, possession of a dangerous weapon and driving on a suspended license.
Santa Barbara is 90 miles northwest of Los Angeles.
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