PORTLAND, Ore. -- Portland police released surveillance photos of two suspects in a string of bar and tavern robberies that began in early June.

The suspects were armed with either handguns or knives during the robberies, according to police. Both were described as black men with dark complexions in their 20s.

The first suspect is between between six feet and 6-foot-3 and 225 pounds with a small colored tattoo on his left forearm.

The other suspect is 5-foot-6 to 5-foot-8 with a medium build.

Photos: Portland bar robbery suspects

Police believe the men are responsible for three bar robberies early Monday morning..

Officers were called at 12:49 a.m. to the Greeley Avenue Bar & Grill, at 5241 N. Greeley Avenue. Witnesses said two black men, one with a gun, demanded money, cellphones and wallets. No one was injured.

A second call came in at 2:04 a.m. from the Sandy Hut, at 1430 NE Sandy Blvd. A black man with a gun demanded money. A security worker "intervened" and the suspect ran out eastbound on Couch Street with another black man, police said.

The Hilt, at 1934 NE Alberta Street, reported a robbery at 2:28 a.m. Two armed black men demanded money, cell phones and wallets. No one was injured.

Anyone with information about the robberies is asked to contact Detective Tracy Chamberlin at 503-823-4783 or Tracy.Chamberlin@portlandoregon.gov.

Crime Stoppers of Oregon is offering a reward of at least $250 for anyone who reports a convicted felon or juvenile in possession of a firearm. Submit an online tip here or 503-823-HELP (4357).

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