DoubleTree hotel in downtown Boston evacuated due to carbon monoxide

A hotel in downtown Boston was evacuated Tuesday night due to a carbon monoxide issue.

The Boston Fire Department said in a tweet shortly after 10:15 p.m. that all rooms of the DoubleTree hotel on Washington Street had been evacuated, citing high levels of carbon monoxide.

There are more than 250 rooms in the hotel.

Fire officials said shortly after midnight that the source of the problem had been found and mitigated, the levels had dropped and the over 500 guests were allowed to return to their rooms.