Three objects that could be vehicles were detected underwater where part of a bridge collapsed early Friday after being hit by a boat.

After more than seven hours of searching, eight ships have found three objects beneath water via sonar technology around the site, according to Guangdong Maritime Bureau.

The ships will continue searching between 30 meters and 60 meters underwater around the collapsed Jiujiang Bridge to determine what the objects are and their locations.

The bridge in Foshan, Guangdong Province, collapsed after being hit by a boat laden with sand at about 5:10 a.m. on Friday,

All the 10 crew members were saved shortly after the boat became partially submerged, and two injured crewmen were released from hospital after being treated for bruises.

Rescuers are concerned that some vehicles may have fallen from the bridge into the river, but officials said that was not likely much traffic on the 1,600-meter-long bridge as the accident took place in the early morning.