The FBI says it's offering a reward for information about a serial bank robber — nicknamed the "Double Hat Bandit" — who's suspected in at least 13 heists, including four in Oregon.

The FBI is offering as much as $10,000 for information that leads to the identification, arrest and conviction of the bandit, the agency said in a news release Thursday. He's accused of hitting bank branches inside grocery stores in five states between December 2016 and late July.

The bandit, who earned his moniker for wearing two hats during his alleged heists, is most recently suspected of robbing a Boise bank in late July. He's suspected of hitting a U.S. Bank in Milwaukie, Wells Fargo in Southeast Portland and U.S. Bank in Eugene in January. He's also suspected of robbing the same Southeast Portland bank in late June.

He usually shows a note to a teller, the FBI said. The agency said he also showed "a small handgun in his waistband" in four of the heists and "should be considered armed and dangerous."

He was seen in a blue-gray Chevrolet Malibu — or a similar car — with New Mexico plates after a June 27 robbery in Spokane. Law enforcement agencies in Oregon, Washington, Idaho, Utah and Colorado are involved in the investigation.

Metro Denver Crime Stoppers is offering an additional reward of as much as $2,000, the FBI said.

The FBI asks anyone who has information about the bandit to call its tip line, 801-579-6480.

— The Oregonian/OregonLive