The Coast Guard tested the tugboat captain, a barge crew member and the camp counselor for alcohol or drugs. None tested positive, the agency said.

The owners of a sailboat and barge that collided in Biscayne Bay on Monday, killing two young girls and critically injuring two other girls, are working with commercial salvage to draft a plan to have both vessels removed, according to the U.S. Coast Guard.

CBS News Miami’s Jim Berry examines what led a barge to collide with a sailboat full of summer campers in Biscayne Bay earlier this week. He’s joined by CBS News Miami’s Chelsea Jones to determine how the investigation will continue.