Another piece of glass has fallen from a Toronto highrise building, crashing to the ground Tuesday morning in what is becoming a frighteningly common scenario downtown.

The glass fell around 11:20 a.m. at the corner of Bay Street and Grosvenor Street during repairs at a condo, police said. The glass, which one witness said tumbled from 45 floors above, reportedly hit some parked cars below.

Colin Cook, who was in the north tower looking south at the building at 38 Grenville Street, said it appeared as though the glass had fallen from the top floor while crews were working to remove tempered glass from a balcony.

Cook added it was the same Murano Condos tower in which a pane of glass had fallen a month earlier, cutting a pedestrian's arm.

"We saw it shatter and just fall down on Bay Street," Cook said. "It fragmented in the air, so my guess is it cracked while [workers] were holding it."

Bay was closed in both directions between College Street and Grosvenor as a precaution. The area is being cleaned up.

There have so far been no reports of injuries.

The condo developer, Lanterra Developments, had announced last month it would have workers replace all tempered glass in its condos' balconies following incidents of falling panes downtown.

Tuesday's incident was the fourth case of falling glass from a condo building in less than a month. On three separate occasions since Aug. 13, glass fell from condo towers built by Lanterra.

A condo near Bloor Street West and Bedford Road lost glass on two occasions.

The third incident involved the south tower at 38 Grenville St. A woman walking along Bay St. was slightly injured in that incident.