A 28-year-old Keighley woman and her male companion drowned in an underground cave when they were trapped by rising water, rescuers have said.

The pair, who have not yet been named by the police, were caught in a fast-flowing stream swollen by heavy rainfall.

The woman, understood to be from the Riddlesden area, was on the caving expedition with a 33-year-old man from Darlington, County Durham. He is believed to have worked as an engineer.

Their bodies were found early yesterday in Lower Long Churn in the Yorkshire Dales National Park, a cave popular with adventure holiday groups and parties of school children.

North Yorkshire Police began searching for the man after his wife raised the alarm when he failed to return home.

Bradford school teacher Phil Haigh, who led the cave rescue bid, said the pair were caught by rising water.

Mr Haigh, head of geography at Nab Wood School, Cottingley, was in charge of a 19-strong team from The Cave Rescue Organisation.

The group found the bodies at 3.20am and recovered them from the cave.

Mr Haigh said the pair were found 60 to 70 metres down Lower Long Churn, a passage that connects to the famous Alum Pot cave system.

Mr Haigh, a cave rescuer for more than 25 years, said: "It is a tragic accident that is particularly poignant at this time of the year.

"As cavers ourselves, we have a particular sympathy and empathy with the bereaved families and send our condolences to them."

Mr Haigh said that water could rise in a cave several hours after rain had stopped.

Rae Lonsdale, a duty controller with The Cave Rescue Organisation, said the team was mobilised after police found the man's car at Selside, a hamlet in the parish of Horton-in-Ribblesdale.

Mr Lonsdale, of Langcliffe, near Settle, said the water level in the cave was high after hours of heavy rain.

"The woman said her husband had gone caving and when police found his car in Ribblesdale, we were called out.

"It was half an hour after midnight and still raining. The water levels were high but if you know the caving system there are ways to keep out of much of it.

"Nineteen of our members turned out. Three stayed at our Clapham base and 16 went to the cave," Mr Lonsdale said.

He said there is a fast-flowing underground river in the cave but accidents were rare.

"When somebody is reported overdue and missing underground, we always go out with high hopes of finding them OK. Very sadly, this wasn't the case on this occasion.

"Whatever anyone says, caving is a safe sport and accidents like this are, fortunately, relatively rare.

"A tremendous number of children from the Bradford area visit this cave for their first experience of wild caving but their leaders would not take young people underground in weather like this," he said.

Inspector Mike Thompson, of North Yorkshire Police, said: "We responded, along with The Cave Rescue Organisation, to a report a husband had not returned home.

"At 3.22am yesterday two bodies were found at a spot known as Lower Long Churn."

He said there were no suspicious circumstances.

The Alum Pot system was discovered in 1848 and continues for 1,200 feet under the moors.

Janet Graham, committee member of the Council of Northern Caving Clubs, said the cave was safe under normal conditions.

"It is an active stream with pools and it could catch people out. They must be aware of the forecast as conditions can be deceptive," said Mrs Graham, of Giggleswick.

Steve Pullen, ward councillor for Riddlesden, said: "This is a tragedy at any time but especially at Christmas."

Councillor Pullen (Lab, Keighley East) said the deaths were all the more moving for him because he himself had lost a relative in a caving accident.