BOSTON — A man was bludgeoned in the head with a hammer during a terrifying early morning attack outside a bakery in East Boston — in the very city Mayor Michelle Wu continues to call “America’s safest.”

According to Boston police, the victim was entering a bakery in Maverick Square around 6:30 a.m. Tuesday when a stranger approached and asked to borrow his cellphone. The man said he didn’t have one and went inside the store.

But when he stepped back outside, the suspect allegedly struck him in the head with a hammer and fled the scene.

The victim was hospitalized with serious but non-life-threatening injuries, police said.

Officers later distributed images of the suspect and identified him as 37-year-old Eric Vargas of East Boston. He was found sitting on the steps of a building on Paris Street the following night and placed under arrest without incident.

Vargas is expected to be arraigned in East Boston District Court on one count of assault and battery with a dangerous weapon.

The incident adds to growing public concern about random violence across the city — even as Mayor Wu continues to tout Boston’s safety rankings.