A building has "collapsed" into an underground station - as part of the biggest disaster training exercise ever seen in Europe.
The staged scenario is being carried out to prepare specialist emergency crews for a large-scale operation.
The Exercise Unified Response, coordinated by the London Fire Brigade, sees the blue light services working side-by-side with more than 70 partner agencies including local councils, utility companies and specialist search and rescue teams to respond to the disaster.
Disaster victim identification (DVI) teams from all UK police regions are working alongside other forensic specialists.
In total, more than 250 personnel are working at the scene in Kent where the Tube station was mocked up and in a specially constructed temporary mortuary during the four-day exercise.
In recent years specially trained teams from around the UK have been deployed to assist in the downing of Malaysia Airlines Flight MH17 in July 2014 and the Shoreham Air Crash in August last year.
Chief Constable Debbie Simpson, of the National Police Chiefs, said: "Victim identification is never a pleasant subject to discuss but it is unfortunately a reality. When disaster strikes families need to be confident that the authorities are doing everything they can to identify their loved ones in a dignified and respectful way, whilst supporting any criminal investigation.
"Importantly this process cannot be hurried. As frustrating as this can sometimes be, especially in a world of fast paced mainstream and social media, we have to be meticulous in our approach to ensure we achieve reliable scientific identification.
"It's not often we get to test working practices on such a scale and it's really positive to see so many of our European colleagues involved. Effective evaluation and debriefing will help highlight good practice and any areas for development."
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