BOISE -- The Federal Bureau of Investigation is enlisting the public's help in tracking down the man who robbed three banks and credit unions in the Boise area over the last six months.

The unidentified man - nicknamed "The Great Outdoors Bandit" by the FBI because of his "outdoorsy" attire - struck again in Orem, Utah two weeks ago, investigators say.

The robber first struck Dec. 21, 2016 at the the U.S. Bank located inside the Albertsons store at 10500 West Overland Road in Boise. According to the FBI, he waited in line before approaching the teller with a note. After getting the money, the man ran away on foot.

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Fifteen minutes later, he struck again at the Idaho Central Credit Union on South Celebration Avenue in Meridian, once more walking up to a teller with a note demanding money. The man did not speak, investigators said, but again took the money and ran away.

The robber next targeted the Bank of the West location on West Emerald Street in Boise March 24. This time, the robber -confirmed to be the same man as in the first two robberies - showed the teller a note and put the money into a brown bag he has taken with him.

According to the FBI, the Great Outdoors Bandit was seen getting a dark-colored, two-door coupe - possibly a Subaru Outback or Legacy - after the March robbery.

Using the same technique of showing a note to the teller, the unidentified man robbed the Alpine Credit Union in Orem Utah May 24. Once more, he put the cash into a brown paper bag and ran away.

GALLERY: The Great Outdoors Bandit wanted by FBI

During each of the hold-ups. the robber wore a green Cabela's baseball cap, and large black sunglasses. During one of the robberies in Boise, he also wore a black hoodie with the Pi symbol on the front.

The man is described as 5'4" to 5'6" and approximately 140 to 160 pounds, with a skinny build. His race is unknown, but the investigators say he may be Native American, Hispanic or Middle Eastern.

The robber is between 30 and 50 years old, and has black hair, according to investigators.

The FBI is offering a reward of up to $10,000 for information that leads to the arrest and conviction of the culprit. Anyone who recognizes him or has any information about the case should call the FBI's toll-free tip line at (833) 291-4306 or submit a tip at