Tokyo - A fire before dawn Wednesday in an Osaka sex shop left 15 patrons dead, emergency authorities said.

The blaze broke out in a video sex shop on the ground floor of a seven-storey building. The bodies of 15 men were found in individual, private viewing cabins after the fire, which took about an hour and a half to extinguish, Japanese media reported.

Another 10 men and one woman were rescued from the blaze, with three of them suffering serious injuries.

The cause of the fire was not immediately known. (dpa)