AUGUSTA — A Waterville man will spend seven years in prison for robbing a bank and making a bomb threat that forced an evacuation of a swath of the city’s downtown.

William Bruce Adamchak, 49, pleaded guilty Tuesday in Kennebec County Superior to charges of robbery and terrorizing all related to the robbery of a Waterville branch of Bank of America on Nov. 7.

He was arrested by police, with the assistance of bystanders, within half an hour of the robbery and still in possession of the $2,200 that he got from a teller, according to court records.

Assistant District Attorney Paul Rucha said Adamchak gave a bank teller a deposit slip indicating he wanted cash and no dye bags. The note also suggested he had a bomb.

“He held a cellphone, so she (the teller) thought that it was a detonator,” Rucha said.

When Adamchak fled the bank with the cash he was given, he left behind a backpack, forcing authorities to evacuate the bank out of fear that a bomb might be inside, Rucha said.

A Maine State Police bomb squad and a state fire marshal examined the bag inside the bank and determined it contained no explosives. The area was cleared after several hours.

A bank patron who saw what was happening followed the robber from the bank. Adamchak was caught shortly after the 3 p.m. robbery when the patron tracked him up Main Street, across The Concourse and finally to The Big Apple on Elm Street, where he was confronted by police.

When Adamchak was confronted by a police officer and fled, three men who were watching nearby got in front of him and held him, according to police. Police said they found Adamchak in possession the same amount of money that had taken from the bank.

At the time of the robbery, Adamchak was on probation for convictions on forgery and theft charges and failure to appear in court. He was initially was arrested on three outstanding warrants and taken to jail.

Betty Adams — 621-5631

badams@centralmaine.com