By George P. Hassett

Someone stole 475 pounds of cast iron metal off the new pavement of Josephine Avenue Sunday night, according to police, and no one saw a thing.

The suspect traveled along Josephine Avenue, from Kidder to Broadway, and stole 20 manhole and 15 water gate covers, police said.

The manhole covers weigh at least 20 pounds and the water gate covers weigh five pounds, said Somerville Police Captain Paul Upton. They had been taken from the street and stacked on top of one another as work crews repaved the road and replaced sewer infrastructure, according to city spokeswoman Lesley Delaney Hawkins.

“They’re not light,” Upton said. “It took some time for it to happen.”

The police do not have a suspect. Upton said residents have not been able to provide police with information. None, he said, reported hearing or seeing 475 pounds of metal taken from their street between 5 and 10 p.m.

Last night police sent out an automated call to every home within four square blocks of Josephine Avenue asking for help.

“Not only is this a crime but it presented a serious safety concern for anyone walking or driving along this street,” Upton said in the message.

The weighty heist begs the question: how did it happen? Any scenario it seems would involve a vehicle with a lot of storage room. But Upton said there are other possibilities.

“It’s not inconceivable that someone living right on the street rolled them into their backyard,” he said.

“It’s unlikely but you can’t rule any possibility out.”

Police are asking anyone with information to contact Somerville Police Detective Ernest Nadile at 617 625-1600, extension 7235.  They said all leads will be kept confidential.