UPDATE - 45 people injured, 3 people badly injured and 3 Engineers Burli...

VIA Rail says three people killed in a passenger train derailment in Burlington on Sunday afternoon were employees riding in the locomotive. Dozens of passengers were injured after the eastbound train derailed around 3:30 p.m. Emergency crews worked frantically to free about 60 trapped passengers from the wreckage. One of the derailed train cars appears to have crashed into a small building near the train tracks and came to a rest on its side. The other two derailed cars formed a V-shape across the train tracks, but remained upright. At least two patients were transported to Hamilton General Hospital. The hospital has declared code orange, which signals an external disaster. Air ambulances have rushed some other injured passengers to hospitals in London and Toronto. Dozens of land ambulances also converged on the scene. Toronto EMS has sent a crew of paramedics to Burlington on a bus. Staff Sgt. Roger Wilkie of Halton Regional Police told CTV News Channel the eastbound train from the Niagara region was headed to Toronto when the derailment occurred around 3:30 p.m. near Plains and King roads in Burlington. Burlington is about 60 kilometres west of Toronto. The derailment occurred in an industrial area, but there are residential homes and businesses nearby. The train was carrying 75 passengers and four crew members, Wilkie said. It was not immediately clear what caused the derailment. It was dry and sunny in the area at the time. The Transportation Safety Board of Canada is sending a team of investigators to Burlington to pinpoint the cause of the disaster. The derailment is affecting GO Train service on the Lakeshore West line. GO is advising passengers that buses will operate between Burlington and Aldershot stations. The derailment is blocking train tracks east of Aldershot.