Three of the injured have been admitted to the Medical College Hospital and one to the General Hospital where their condition was stable, hospital sources said.
At least 10 workers were feared trapped when a portion of the building, one of the oldest lodges located near the Central Railway station and the main bus terminal in the Thampannur locality, collapsed.
Fire force, police and army personnel were engaged in rescue operations.
Eyewitness said huge concrete slabs came crashing down as workers were engaged in the construction activities.
Crane and other equipment for removal of rubbles and blocks of concrete have been brought to the site.
Published 01 February 2010, 15:29 IST