TEL AVIV (Reuters) - A man apparently suffering from mental health problems stabbed a security guard at the U.S. embassy in Tel Aviv on Tuesday and was apprehended, police said.

"A Mazda car stopped next to the U.S. embassy and a man got out carrying a red bag and a pitchfork," said David Cohen, 48, who told Reuters he witnessed the incident while jogging along Tel Aviv's Mediterranean promenade.

"He began to run toward the security guards. They saw him, took their guns out and told him to get down on the ground," Cohen said.

"He continued running and then they fired in the air and ordered him again to lie down. He continued to advance. They jumped on him and took his bag away."

Police said one of the guards was slightly wounded and the attacker was taken into custody.

"It appears he was mentally unbalanced," Tel Aviv police chief Yoram Ohayon told reporters.

Israel Radio said the assailant was a 41-year-old Israeli with a criminal record.

(Writing by Ori Lewis, Reporting by Maayan Lubell and Baz Ratner, Editing by Jeffrey Heller)