A fire began blazing through a vacant building at 115 Mill Street in Belmont early Monday morning shortly after 3 a.m.
The engulfed property is an old and abandoned psychiatric building located on the McLean Hospital campus in Belmont, according to the Belmont Fire Department.
Officials say the building has been vacant for 10 years but once held patients.
The BFD reported the two-alarm fire can be viewed from a quarter of a mile away, and fire crews were still dousing hot spots late into the morning.
Crews are keeping people away from the building in the event it will collapse.
Cambridge fire crews have come to assist Belmont firefighters.
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