Eleven kidnapped Colombian politicians held hostage for five years have been killed in the crossfire after the army attacked the jungle camp where they were being kept, it was reported today.

A statement purportedly from the Revolutionary Armed Forces of Colombia, or Farc, the country's biggest rebel group, says that 11 of the 12 provincial deputies being held were killed in the crossfire after an “unidentified military group" attacked the rebel camp on June 18.

The interior minister and a close adviser to President Alvaro Uribe told Colombian media that they had no information on the reported deaths. There was no way to independently confirm the report.

“We are waiting for confirmation,” wept Fabiola Perdomo, the wife of one of those reported dead. “I’m totally lost, we don’t know what we’re going to do.”

The 12 regional politicians were kidnapped in broad daylight in April 2002 in the city of Cali, capital of the state of Valle del Cauca.

Their families have repeatedly begged the government not to take military action in an attempt to free the large number of hostages held by Farc, for fear of exactly what now appears to have happened.

The statement said that just one survived, Sigifredo Lopez, who was not with the others at the time of the attack.

“To the families of the dead deputies, we offer our deepest condolences. We will do all in our power to help them recover the bodies as soon as possible,” according to the statement.

The report did not say where the clash occurred, saying only that there had been increased operations by the military in the area in recent weeks.

General Freddy Padilla, the head of Colombia’s armed forces, said in a statement: “Military intelligence has not had any information where the deputies (of the province) of Valle del Cauca were being held by the Farc, and so has not ordered any rescue missions.”

As Mr Uribe’s government has put the Farc on the defensive, the group has limited its contacts with most news organisations, but has continued to use Anncol, a Danish website, to divulge information. The Farc’s own website carried no information on the deputies’ fate.

The 12 deputies are among 60 prominent hostages held by the Farc, along with former presidential candidate Ingrid Betancourt and three kidnapped US defence contractors, which the group wants to exchange for all imprisoned Farc rebels in Colombia and the United States.

Over the years, the families of the 12 kidnapped deputies have pressured the government for such an agreement and criticised occasional government statements that argued for military rescues, fearing their loved ones would be slaughtered in the crossfire.

In what he called “a gesture of good faith" for a possible agreement, Mr Uribe freed the highest ranking Farc rebel held in prison earlier this month and is preparing the release of another 150 Farc rebels.

The rebels have rejected the move, demanding the temporary demilitarisation of a zone in southwest Colombia for a complete swap of hostages for prisoners, something Mr Uribe has said he will not do. The statement described him as "insanely intransigent".

This year, two of the 60 prominent hostages have fled FARC captivity, including the current foreign minister and a police officer who spent nearly nine years in rebel hands.

The website that reported the deaths is registered in Copenhagen, Denmark, under the name of Leif Larsen.

“I have no knowledge of what is on the Web ... I didn’t know what you told me about the lawmakers being killed,” said Mr Larsen, adding: “It seems that they (Farc) will get the blame for that (the lawmakers being killed)."

Mr Larsen, 82, denied being the website’s owner.

Times Recommends

• Should Knox’s trial even have reached the courtroom?
• 'Was it real?' The US bailout nightmare
• Iranian opposition plays the long game