LYNN-A New Bedford man with a long criminal rap sheet was arrested Monday in connection with the Aug. 28 robbery of Sovereign Bank on Exchange Street as well as a separate bank robbery in Taunton.Police say Glenn Porter, 40, of 244 Phillips Ave., New Bedford, demanded “fifties and hundreds” from bank tellers during both heists.Porter, whose mother lives in Lynn’s Liberty Square, only one block away from the Sovereign Bank, was arrested around 4 p.m. in New Bedford. Police say he robbed the Bristol County Savings Bank on County Street in Taunton around 10:15 a.m. Monday.Investigators say both robberies were conducted in a similar manner. No weapons and no note were displayed to the bank tellers. The suspect verbally demanded money and said during both heists, “Give me fifties and hundreds.”However, he also said to the female teller in Lynn, “Give it to me or I’ll kill you!” according to a police report.After viewing a video surveillance tape of the robbery, Lynn police and the FBI quickly identified the suspect as Porter, “a known drug user,” who was allegedly wearing sunglasses and a baseball cap at the time of the heist, police said.Police believe that Porter walked to his mother’s home moments after the robbery, where he called for a cab from Garcia Taxi. Cops found a pair of sunglasses on the sidewalk halfway between the bank and Liberty Square, police said.During the Lynn robbery, Porter allegedly left the bank with $13,550 in cash, according to a police report. Police did not say how much was stolen from the Taunton bank.Shortly after a Garcia Taxi driver picked up Porter, police called the driver’s cell phone and he said Porter was sitting in the cab, police said.According to a police report, attempts were made to have the cab stopped by area law enforcement but Porter was able to get out of the taxi somewhere in Fall River.Police say Porter paid the $200 cab fare with two $100 bills. They added that during the trip, the driver observed Porter holding an envelope with a large amount of cash. The driver also said Porter appeared nervous, made four cell phone calls during the ride and snorted cocaine, police said.Investigators also used video surveillance at 7 Liberty Sq., the address of Porter’s mother, during the investigation. They believe he ditched his sunglasses and baseball cap after leaving the bank.Porter has a criminal record containing 28 court arraignments since 1986.Two of those arraignments were for very serious charges. On March 10, 1988, he was arraigned in South Boston District Court for armed robbery, a firearms violation and receiving stolen property. And on April 10, 2006, he was arraigned on a single charge of home invasion.The vast majority of Porter’s arraignments have been at Lynn and Salem district courts, primarily for drugs and motor vehicle charges, but also for misusing credit cards and forgery.He was charged in December 2005, August 2003 and May 1996 for being a “compulsory motor vehicle insurance violator” in Lynn.