Two divers presumed to have died after they failed to resurface while exploring a wreck off the Cornish coast.
The pair went missing while diving around the HMS Scylla which was sunk in 2004 to create an offshore reef.
A major search and rescue operation was launched off Whitsand Bay on Friday and continued into the early hours of Saturday morning.
It is understood the alarm was raised by another member of the diving party after the missing pair did not return to the surface.
James Instance from Falmouth Coastguard, said it was suspected the pair had died, but that had not been confirmed, the BBC has reported.
Mr Instance told the BBC: “We swang into action a search and rescue plan involving the rescue helicopter from Newquay, the Looe and Plymouth inshore lifeboats, Plymouth all-weather lifeboat, a police launch and other vessels. The dive boat also remained on scene.
“We were unable to locate or find anybody.
“Our thoughts are with the people who were in the dive party who are dealing with what is a very traumatic experience.”
While the recovery effort is ongoing leisure divers are asked to avoid the area around HMS Scylla.