A sixth Briton has been confirmed dead following the Kenyan shopping centre atrocity as the Foreign Office said it could not rule out the possibility of further British casualties.
Some 67 people were killed in the deadly attack on the upmarket Nairobi mall and d ozens of people are still reported missing.
Earlier this week Prime Minister David Cameron suggested six Britons may have died in the catastrophe and the Foreign Office confirmed this figure today. The person's identity has not been revealed.
A spokesman said: "FCO can confirm a sixth British national has been identified amongst those killed in the tragedy in Nairobi. We are providing consular assistance.
"We have no information at this time that any further British nationals have been killed although we cannot rule out the potential for further British casualties and we continue to stay in close contact with the Kenyan authorities as their investigations continue."
News of the sixth death was announced as a harrowing video emerged showing medics rushing to help the injured shortly after the the four-day stand-off began.
Rescuers can be seen treating the wounded as others wail or cry out for help, while bodies are visible on the pavement outside the Westgate mall.
In the footage, filmed by the Kenyan Red Cross, slabs of concrete can be seen on top of crushed cars and clips show rows of scorched vehicles.
The video was released seven days after terrorists stormed the mall but there are still no clear details relating to the perpetrators.
The al Qaida-linked Somali Islamic extremist group al-Shabab has claimed responsibility for the assault and earlier this week Kenyan authorities claimed a woman was involved.
This suggestion has led to speculation that British terrorist suspect Samantha Lewthwaite - who was married to the July 7 bomber Jermaine Lindsay - may have some connection with the attack.
Dubbed the ''White Widow'', Lewthwaite is known to be in East Africa and is wanted over alleged links to a terrorist cell that planned to bomb the country's coastal resorts. Interpol issued a notice asking for help in capturing the 29-year-old fugitive over the 2011 plot.
Tales of horror have emerged over the past few days as survivors have come forward to detail their ordeals at the Westgate mall.
Mitul Shah, 38, a London-born father of one caught up in the siege, was yesterday hailed a "hero and a star" for reportedly offering himself as a hostage to allow children to escape from militants.
The youngsters were taking part in a televised cooking competition sponsored by his company when the terrorists descended on the shopping centre.
Investigators have recovered a vehicle believed to have been used by the terrorists who led the attack.
At least five of the militants died in the mall and a nother 11 are being held by Kenyan authorities - including at least seven who are thought to have been arrested at the airport.
International forensic experts, including teams from Scotland Yard, the United States, Israel, Germany and Canada, are helping sift through the debris for clues.