Prime Minister David Cameron confirms that three British nationals have been killed in the Algerian hostage crisis and that a further three, along with a British resident, are missing and feared dead.

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Algerian special forces clearing the plant today made the grim discovery of 25 more bodies, indicating that the hostage death toll may rise.

The Algerian forces also captured five militants alive, bringing the number of militants believed to have participated in the attack up to 37.

In total, 685 Algerian and 107 foreign workers have survived the crisis. However, 23 hostages have already been confirmed dead.

The prime minister said that the three hostages had been killed following the four day stand-off in the desert which dramatically came to an end on Saturday.

Barring the missing four, the 22 British nationals who survived the ordeal are now safely back in the UK.

"I know the whole country will want to join with me in sending our sympathy and our condolences to the families who have undergone an absolutely dreadful ordeal," Mr Cameron said.

The Foreign Office said that the figures announced by the prime minister included the Briton killed on Wednesday in the initial raid by Islamist militants.

Meanwhile, Scotland's First Minister Alex Salmond said: "We know that two Scots, or people with immediate Scottish family connections, are believed to have been killed. The two families concerned were informed by police yesterday.

"We know that eight Scottish survivors are all now back in the UK. While eight families can thankfully welcome home their loved ones, our thoughts must be with the families of those who may have been lost in Algeria."

Despite the high death toll - with 23 hostages and 32 terrorists known to have died - the prime minister refused to criticise the uncompromising stance taken by the Algerian government.

"The responsibility for these deaths lies squarely with the terrorists who launched these vicious and cowardly attacks," he said.

"When you are dealing with a terrorist incident on this scale with up to 30 terrorists it is extremely difficult to respond and get this right in every respect.

Survivor tells of daring escape
BP employee Alan Wright, 37, hid from terrorists for 24 hours before making a break for freedom. The father of two said today that he hid in an office before joining Algerian colleagues in cutting their way through a fence and fleeing.
He told Sky News: "If you have been captured, there's pretty much no escape and it is going to take a miracle to get you out".
Mr Wright said the men were surprisingly calm during the attack. "Everyone went into safe mode", he said, assessing what they were going to do and stocking up on supplies. The group got a satellite phone, taped up their window and locked the door.
The group hid from the terrorists who were attempting to clear the building and coax hostages out.
Making a break for it the following morning, they had no way of telling the Algerian forces apart from the terrorists as they were dressed the same, he said.
"We got about a kilometre into the desert and you can see the military point with eight or nine military personnel with guns pointing into our spot but also that they had identified us and were making tracks to come our way. Then you think 'Is it the terrorists or is it the gendarmes?'
"And for 20 minutes you're still not sure - we're down on your hands and knees with our hands up."
He applauded the courage of his Algerian colleagues in helping the ex-pats escape and added that his thoughts were with those who had been killed.

'Stark reminder of terrorism threat'

Mr Cameron said the attack was a "stark reminder" of the continuing terrorist threat and vowed to use Britain's chairmanship of the G8 to ensure that it was right at the top of the international agenda.

"This is a global threat and it will require a global response. It will require a response that is about years, even decades, rather than months," he said.

"It requires a response that is patient and painstaking, that is tough but also intelligent, but above all has an absolutely iron resolve and that is what we will deliver over these coming years.

"We have had successes in recent years in reducing the threat from some part of the world, but the threat has grown particularly in north Africa," he added.

President Barack Obama said the US was ready to provide whatever assistance was needed in the wake of the attack.

"This attack is another reminder of the threat posed by al-Qaeda and other violent extremist groups in north Africa," he said in a statement.

"In the coming days, we will remain in close touch with the government of Algeria to gain a fuller understanding of what took place so that we can work together to prevent tragedies like this in the future."

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