Sao Paulo, Jul 28 (IANS): Eight people were killed in a grain silo explosion at an agro-industrial cooperative in southern Brazil's Parana state, the local fire department said.

The bodies of six people were found early Thursday by rescuers searching through the rubble of the collapsed structure. The first two victims were found following the blast on Wednesday afternoon at the silo located in the town of Palotina.

A dozen people were also injured, according to the Parana Fire Department, which said the fatal victims were in a tunnel that connects different parts of the silo, Xinhua news agency reported.

Employees of the cooperative, the second largest in Parana, were conducting maintenance work when the blast occurred. The cause has yet to be determined.

The sound of the explosion was heard miles away and the impact shattered windows of nearby properties, witnesses told Brazil's Globo news channel.

Nearly 35 firefighters and sniffer dogs were dispatched to search for survivors and retrieve the bodies of the victims.