The City of Waltham is offering a $5,000 reward for information that leads to an arrest and conviction in a series of unprovoked attacks on male pedestrians walking alone, officials said Tuesday.
At least 10 men — including a U.S. Postal Service mail carrier — have been targeted since Nov. 10, Waltham Police Chief Keith MacPherson said at a news conference. Some have required hospitalization, Mayor Jeannette McCarthy said.
In every case, it appears that the assailant, whose face is covered, sneaks up on victims from behind after dark, the chief said. Police think the attacker uses some sort of weapon to strike the victims.
Police on Saturday released surveillance images of a possible suspect.
“The motive is somewhat in question but it appears to be a thrill of the assault, or someone who’s very violent and enjoys seeing someone hurt by this,” MacPherson said. “There’s never been a robbery — it’s always been just an assault and the assailant takes off.”
McCarthy urged residents not to walk alone and stick to well-lit areas. The city also shared safety tips from the police department on its Facebook page Wednesday.