LAC-MEGANTIC, Quebec (AP) — Hazardous conditions are getting in the way of firefighters' efforts to search for some 40 people still missing after the explosion of a runaway oil tanker train in Quebec over the weekend. At least five others were killed.

Police say there was no additional searching overnight because the situation remained too dangerous. A police spokesman says only a small part of the devastated scene has been searched, as firefighters make sure all of the flames are out.

Many of the missing are believed to have been drinking at a popular downtown bar when the explosions occurred. Searchers still haven't been able to reach that area.

Today, firefighters are focusing their efforts on two rail cars filled with oil. They're dousing them with water and foam, to try to keep them from overheating and exploding.

All but one of the train's 73 tanker cars were carrying oil when they somehow came loose Saturday morning. They sped downhill nearly seven miles into a town near the border with Maine and derailed. At least five of the cars exploded.

About a third of the 6,000 residents were forced from their homes by the explosion and flames.

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058-a-15-(Maxime Picard (Pee-KAR'), who was inside the now destroyed bar when the derailment happened, in interview)-"buildings, really crazy"-Maxime Picard, who was inside a now destroyed bar, says his car was gone after the deraliment but he feels lucky to be alive.COURTESY: The Canadian Press ((mandatory on-air credit)) (8 Jul 2013)

<<CUT *058 (07/08/13)££ 00:15 "buildings, really crazy"

061-a-13-(Donald Ross, investigator, Canadian Transportation Safety Board, in interview)-"to knee deep"-Canadian Transportation Safety Board investigator Donald Ross says they've got a lot of digging out to do before they can really start to investigate. COURTESY: The Canadian Press ((mandatory on-air credit)) (8 Jul 2013)

<<CUT *061 (07/08/13)££ 00:13 "to knee deep"

GRAPHICSBANK: Wreckage of railway cars that were carrying crude oil after derailing, burning and destroying the nearby town, Lac Megantic, Quebec, Canada, aerial photo on texture, partial graphic (7 Jul 2013)

GRAPHICSBANK: Canada topographic relief map, with montreal, Lac Megantic locator, with lettering, finished graphic (8 Jul 2013)

APPHOTO RYR109: Fire fighters continue to water smoldering rubble Sunday, July 7, 2013 in Lac Megantic, Quebec. A runaway train derailed Saturday igniting tanker cars carrying crude oil. (AP Photo/THE CANADIAN PRESS,Ryan Remiorz) (7 Jul 2013)

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APPHOTO PCH107: Burnt out tanker cars and the smouldering remains of businesses in downtown of Lac Megantic, Quebec is seen Sunday, July 7, 2013. A runaway train Saturday derailed, igniting explosions and fires that destroyed the downtown district. (AP Photo/The Canadian Press, Paul Chiasson) (7 Jul 2013)

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