A massive air conditioning unit being lifted into place on a 28- story building in Midtown Manhattan on Sunday morning broke free, ricocheting off the tiered building and landing the street below.

Ten people were injured, including two construction workers, none with life-threatening injuries. The other people injured were either pedestrians or occupants of passing cars.

Traffic was restricted to a single lane on Madison Ave. between 38th and 39th streets, during the lifting operation. The building, 261 Madison Ave., is owned by The Sapir Organization.

It was not clear at press time if the accident was a result of crane failure or a problem with the rigging or if the accident occurred during the transfer of the load to the mechanical equipment room.

New York City Buildings Commissioner Rick D. Chandler, speaking at a press conference, said the crane was in good shape and that the site has had active construction permits since February.

The incident is under investigation by the NY Dept. of Buildings.

Permit filings with the New York City Dept. of Buildings indicate that the crane being used was being used and rigged by Skylift Contractor Corp. of Brooklyn, N.Y.  The crane, from Bay Crane of Long Island City, had a 155 + 13-ft boom and a 207-ft jib.

Calls to Skylift for comments were not returned by press time.