It will be necessary to take a long hard look at what we are doing in Sierra Leone

Menzies Campbell MP

Shadow defence secretary Iain Duncan Smith and Liberal Democrat MP Menzies Campbell have made separate calls on the government to reconsider the role of British troops in the country.

But Labour MP Bruce George, chairman of the House of Commons defence select committee said the troops' presence had prevented a great deal of bloodshed.

The 11 members of the Royal Irish Regiment, and a soldier from Sierra Leone, were captured by the rebel group, West Side Boys militia, outside the capital, Freetown.

The troops are part of a 250-strong detachment training government soldiers in the country.

Mr Campbell, Liberal Democrat defence and foreign affairs spokesman, said: "When the troops are safe and well, it will be necessary to take a long hard look at what we are doing in Sierra Leone.

Bruce George: "Your allies are your enemies and then your allies again"

"How long we expect to be there and how we will judge that the military and political objectives have been achieved," he added.

"Sierra Leone is a fragile and dangerous place, and it's essential that the UK is entirely clear minded about its purpose in deploying troops there," he said.

Mr Smith told the BBC: "Whilst obviously one wants to support the British troops out there... we do think that the government needs now to take very, very serious action and have to contemplate whether or not it's worth keeping British troops out there at all."

But Bruce George MP, told the BBC's World at One programme: "I've just come back from my second visit to Sierra Leone in the last few weeks, and we are doing the right thing in being there.

"It's a very volatile situation ... your allies are your enemies and then your allies again."

'Isolated incident'

Mr George said "there would have been a lot more arms chopped off and decent people killed" if British troops had not bent sent in May.

The rebels have made a number of demands including food, medicine and the release of one of their leaders from prison.

The prisoner is known variously as Bomb Blast or General Papa and has been detained in Freetown's central prison for almost two months.

Dr Julius Spencer, Sierra Leone's information minister, said he did not believe the incident should prompt a withdrawal of British troops from Sierra Leone.

He said: "I think that this would be an isolated incident... I really don't think it should have any negative effect on the British troops staying on to do training."