REVERE – Revere police said Tuesday that an overnight sexual assault outside the Revere Beach train station might not be a random attack.At about 8 p.m., a woman ran into the subway station and told a toll collector that she had been assaulted nearby, police said.A female officer responded and interviewed the victim before she was transported to a Boston hospital, according to police.”It is possible that the victim knew the attacker, or was at least familiar with him,” Police Capt. Michael Murphy said.Murphy said the victim was only interviewed briefly by police and investigators plan to re-interview her in the near future.Police canvassed the Revere Beach area shortly after the alleged attack, looking for a white male wearing blue jeans.