Sharjah 24 – AFP: Three people were killed and several others were missing after a "devastating" explosion on Saturday flattened a low-rise apartment block in Jersey, authorities said.

Chief Minister Kristina Moore confirmed at least three fatalities, after a suspected gas leak in the Channel island's port capital St Helier.

Security camera footage showed a fireball engulfing the three-storey, bayside building followed by thick smoke.

The fire was put out but emergency services were conducting "significant work" at the scene, and the rescue operation could take days, police said.

Fire crews mobilised after residents reported smelling gas, Jersey police chief Robin Smith told reporters.

"We have a three-storey building that has completely collapsed -- described from a demolition point of view as a pancake that has dropped almost straight down," he said.