Investigators announced on Wednesday that the massive Dec. 6 fire in "The Block" area of downtown Baltimore was intentionally set.
The Bureau of Alcohol, Tobacco, Firearms and Explosives classified the fire as incendiary, meaning it was set by a person; however, the bureau said it's not sure if the person set the fire on purpose.
"This classification at the present time doesn't necessarily mean we're dealing with a case of arson," said ATF Special Agent Sheree Mixell.
The fire, which occurred just before 4 p.m. in the 400 block of E. Baltimore Street, took hours for firefighters to bring under control. It broke out at the Gayety Show World and caused significant damage to other buildings.
No serious injuries were reported in the fire.
ATF officials said Wednesday that the case isn't concluded, it's just moved into a new phase. No suspects have been identified.
Anyone with information on the case is urged to call 888-ATF-FIRE. A $5,000 reward is being offered.
The ATF estimated there was about $3 million worth of damage, and that's expected to climb.
Fire Department spokesman Kevin Cartwright said the MECU building in that area was damaged, and that the strong wind played a role in the spread of the fire.
Fire officials said 100 firefighters and about 50 pieces of equipment were needed to fight the blaze. Trucks from all over the city were called.
The last time federal ATF officials were involved in a Baltimore city fire was in March 2004 when an ice house the size of four city blocks burned to the ground.
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