ROSEDALE, Md. — Federal investigators are looking into what caused a chemical-carrying CSX train to collide with a garbage truck, derail and explode at a rail crossing in suburban Baltimore on Tuesday. Only one person — the truck driver — was seriously injured and that the chemical fire didn't pose a greater risk to nearby residents.

National Transportation Safety Board officials said late Tuesday that the collision occurred at a private crossing where the only marking was a stop sign. It wasn't clear why the truck was crossing the tracks or whether it was authorized to be there, the Associated Press reported. For the full story, click here.