The man, who carries a skateboard during his robberies, held up a Wells Fargo bank in the Torrey Highlands neighborhood north of San Diego, the Los Angeles Times reported.
FBI officials say they believe the suspect robbed a Comerica Bank in San Diego's Old Town on July 21.
In both instances, the robber demanded money from tellers after showing them a handgun, put the money in his backpack and left.
The man is described as in his late 20s or early 30s, 5 feet 9 to 5 feet 11, about 160 pounds, and wearing a black, hooded sweatshirt and a green paisley bandanna, the Times reported.
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