BANGOR – Convicted murderer Scott W. Allard of Bradford was back behind bars Sunday night after allegedly robbing a Hampden woman Saturday outside the Bangor Mall.

Allard, 37, was being held on $50,000 cash bail at the Penobscot County Jail on a felony robbery charge as well as a charge of criminal threatening with a dangerous weapon.

Allard, recently released on probation from Maine State Prison according to police, also faces a charge of violation of bail conditions. He is being held without bail on that charge.

According to police reports, Allard grabbed the woman’s purse in the parking lot between Filene’s and J.C. Penney at about 6:30 p.m. and attempted to run away. The woman, 43, told police she was fumbling with her car keys when Allard ripped the purse from her arm.

Allard then allegedly drew a knife when confronted by a Dixmont man, who heard the woman scream and intervened.

After Allard put the knife away and attempted to leave the area, the Dixmont man and off-duty Bangor police Officer Jeff Small tackled Allard, who was later taken to jail.

The woman was not injured and recovered her belongings after Allard dropped her purse while running from the scene, according to police.

The robbery charge, the most serious facing Allard, carries with it a maximum 40 years in prison.

Allard, formerly of Winterport, was sentenced in 1984 to 20 years in prison after pleading guilty to felony murder for robbing and shooting to death 46-year-old John Herman on Christmas Eve in 1983.

Herman, a taxi driver, was found dead in his cab in Stockton Springs on Christmas Day. Allard later confessed to killing Herman during a ride from Bangor to Searsport.

A doctor at Allard’s sentencing testified that tests showed his IQ to be 76.

Allard was out on bail for a burglary of a Hampden beauty parlor at the time of the murder.