Somerville, Dorchester men arrested for possession of heroin after Transit Police witness alleged drug deal

Police arrested two men from Somerville and Dorchester after seeing them exchange heroin and cash at the JFK/UMass Red Line T station Friday night, Transit Police said. Plainclothes Transit Police officers reported they overheard Daniel Merrill, 28 of Somerville, saying the words "buying" and "dealer" in a conversation around 9 p.m., police said in a statement. Derick Anderson, 40 of Dorchester, got off a northbound train and briefly spoke with Merrill on the platform.