Sky News has filmed pictures from the rear of the Nairobi shopping mall showing the devastating aftermath of last Saturday's terror attack.
Hundreds of tons of masonry, debris and metal fell down several floors after part of the roof collapsed where the car park was.
The scene has been described as a 'mini Ground Zero' by one forensic expert who spoke to Sky News.
It comes as the Foreign Office said a sixth British national had been confirmed dead following the atrocity in Kenya. The figure had earlier been lowered to five.
Burned out cars were filmed hanging precariously over the edge of the pit and the tin roof of the supermarket atrium was severely damaged.
Below the hole in the roof was where a cookery competition was taking place involving adults and children when the gunmen began shooting at them.
The air conditioning system on the left of the picture was burnt outSome people said the roof collapse was caused by the terrorists starting a fire, others said it was the military who detonated explosives or fired rocket propelled grenades that set off the blaze.
The pictures were filmed from a private property of resident Sukhbir Singh who told Sky News he heard "really loud blasts" and "several gunshots".
He said at the part of the roof which has now fallen down he saw two or three gunmen opening fire towards children, adding "it was really really bad".
He went on: "They just came in and sprayed bullets without talking."
Sky News filmed from the rear of the shopping centreMeanwhile, new footage from the Kenyan Red Cross shows the organisation's staff helping shoppers as they emerged from Westgate Mall during last week's terror attack.
The video was filmed on September 21 - the first day of the siege and just hours after gunmen attacked the mall with assault rifles and grenades.
The organisation's secretary general, Abbas Gullet, is a prominent figure in the footage, not just overseeing the medical care of the injured, but also providing direct medical assistance himself at times.
Mr Gullet's team of medics regularly risked their own lives to bring people out of the shopping centre.
Resident Sukhbir Singh witnessed the terror attackOne man can be seen with is hand on a body covered with a red blanket weeping, while medical teams look on.
Stretchers were repeatedly run in and out of the mall despite the ongoing attack by gunmen.
The Red Cross also helped to transport those who lost their lives in the deadly assault.
Seven days after the attack which left at least 67 people dead, there is still no clear word on the fate of dozens who have been reported missing and no details on the gunmen who carried it out.
Shoppers were told to leave the mall with their hands upAl Shabaab said it carried out the massacre to punish Kenya for sending its troops into Somalia to fight the al Qaeda-linked militant group that had seized large parts of that country for years before being dislodged from the capital, Mogadishu.
The Kenyan Red Cross has said 59 people are unaccounted for, raising fears of bodies in the debris.
President Uhuru Kenyatta's government is facing tough questions after the reported leaking of an intelligence report dated September 13 which warned of an elevated risk and which some top officials said was treated too casually.
Senior security officials told the AFP news agency on condition of anonymity that an intelligence report warning of an attack had been sent to the treasury, interior, foreign affairs and defence ministers, as well as the army chief.
"Briefs were made to them of increasing threat of terrorism and of plans to launch simultaneous attacks in Nairobi and Mombasa around September 13 and 20, 2013," according to the report, quoted in the Nation newspaper.
The report also reportedly said Israel, which has close security ties with Kenya, had warned of plans to attack Israeli property in September, a month which included several Jewish holidays.