INDIANAPOLIS -- Three people were injured when a 60,000 pound, 90-foot crane tipped over into the Athenaeum Monday morning, causing significant damage to the building.

The crane had been parked in the Biergarten at the Rathskeller restaurant, which is in the building in the 400 block of East Michigan Street, as restoration work was done to the building. The incident happened at about 9:45 a.m.

Slideshow: Athenaeum Damage

The crane's boom crashed into the side of the structure at about 9:45 a.m., causing some structural damage directly to the historic building.

Damage to the building from the crane itself was mild, compared to the damage caused when the sprinkler system activated, sending water through the structure.

"The heavy flow of water caused damage to the wood floors and walls, sending pieces of the ceiling and walls to the floor in large chunks," said Indianapolis fire Capt. Rita Burris.

About 150 people inside the building were evacuated. The injuries to the victims were minor, Burris said.

"I heard the large crash," said Milan Wallace, who was across the street. "Several fire trucks, ambulances and police officers started to show up."

The incident happened when the crane's bucket shifted as work was being done on the chimney.

The Athenaeum is a cultural landmark in Indianapolis. It was built in the 1890s.

A structural engineer will examine damage to the building. It was not immediately known how long the Anthenaeum, Rathskeller and YMCA inside the building will be closed.

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