An American adventurer died suddenly Sunday while diving in a flooded iron ore mine near St. John's.

Joe Steffen, 51, a resident of Ohio, was a member of an international dive team that had come to explore the flooded mine on Bell Island in Conception Bay.

RCMP are investigating after he died Sunday afternoon.

Ocean Quest Adventures invited Steffen and other cave divers to explore the flooded No. 2 mine to help promote it as an adventure tourism destination.

The company said in a news release that other divers brought Steffen to the surface and their attempts to revive him were not successful.

RCMP Const. Sean Tipple said Steffen died suddenly, but would not comment on specifics.