Two men who police said caused a disturbance at at the Harp Bar on Causeway Street in the North End were arrested Saturday and charged with more serious crimes. Paulo Anastacio, 28, of Dorchester, was charged with unarmed robbery, and Ruben Pierre, 29, of Medford was charged with destruction of personal property and breach of peace. An officer working a paid detail was first alerted to Anastacio, who police said was causing a disturbance at the bar. An employee told the officer that Anastacio took an undetermined amount of cash from the employee. Witnesses told the officer that Anastacio was passing out the money to other patrons. Meanwhile, police said, the officer witnessed Pierre damaging the front window of the bar. He fled, but was apprehended by another detail officer.