Ann Arbor police are investigating a burglary Tuesday night at an East William Street home where six University of Michigan students live.
A laptop computer, wallet and other items were stolen after someone entered through an unlocked front door between 11:50 p.m. Tuesday and 12:30 a.m. today, a police report said.
Two of the residents were upstairs at the time and told police they may have heard something downstairs, but assumed it was one of their roommates. Their roommates left the door unlocked when they went to the Diag to throw snowballs.
The break-in occurred in the street's 300 block, the report said.

AnnArbor.com