NNA - The collapse of a four-storey building in the coastal city of Marseille in southern France has injured at least five people, but a fire is hampering the efforts of rescue workers in their search for other possible victims, according to "Agence France-Presse".

"A fire broke out in the ruins (of the building), which prevented us from sending dogs and teams to search for possible victims under the rubble," the city's mayor, Benoit Bayan, told reporters.

District police chief Christophe Mirmand told the agency that there was "high suspicion" that an explosion caused the building's collapse and could have been caused by a gas leak," but he emphasized that "we have to remain very careful about the causes at this point."

"The priority is to extinguish the fire and clear the rubble to find people who might be under it," the commander of the Navy's fire brigades said.

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