Updated

A five-story building under construction in Sri Lanka's capital collapsed Thursday, injuring at least 19 people, officials said.

Those injured in the collapse in Colombo have been sent to hospitals, police spokesman Priyantha Jayakody said.

Hundreds of soldiers, police and firefighters were searching for anyone who might be trapped inside the building.

Military spokesman Brig. Roshan Seneviratne said soldiers were in contact with one person trapped.

He said the victim is unable to come out due to a concrete wall and soldiers are talking to him through a hole made through the concrete.

"He is safe and we are trying to rescue him," Seneviratne said.

The reason for the collapse was not immediately known.

Sarath Wimalawardena, an eyewitness who works at a nearby construction site, said the building collapsed with a loud sound that was followed by an enormous cloud of dust. He said people in the area helped evacuate the injured before police and firefighters arrived.