A man tried unsuccessfully to rob a Lafayette bank Tuesday afternoon, police said.

The incident occurred shortly before the 5 p.m. closing time at Mt. Diablo National Bank, 3640 Mt. Diablo Blvd.

The man, who did not display a weapon, fled when he did not get any cash.

Police established a perimeter, including checking BART trains, said Lafayette police Sgt. Roxanne Gruenheid.

The man was last seen running toward Happy Valley Road. He was described as white, in his mid- to late 20s, 5-foot-10, 180 pounds, wearing a tan baseball cap, tan shirt and tan pants.

Anyone who saw the man is asked to call Lafayette police at 925-284-5010.

–– Scott Marshall