TERROR nuts could try to deluge swathes of London with surging flood water by blowing up the Thames Barrier, cops fear.
A targeted blast could affect much of the capital city that it protects – causing many billions of pounds of damage.
The feared attack – which mirrors a plotline in BBC spy drama Spooks – would also leaves tens of thousands homeless.
Army and police bomb disposal teams last week held an emergency meeting with Thames Barrier officials to discuss security.
A counter-terrorism source told the Mirror: “As well as the obvious trade in terror such as killing as many people as possible, the UK’s critical infrastructure is a priority for terrorists.
“Crippling the barrier would have a terrible and long-term effect on the capital and on the rest of the country.”
Senior members of the Metropolitan Police’s marine policing unit were at the meeting.
Currently a 76-officer unit guards the stretch of river that runs from Dartford to Hampton Court.
Counter terrorism veteran and bomb disposal expert Major Chris Hunter said: “Reviewing the security of famous locations such as the Thames Barrier and ensuring that they are protected from attacks is something that’s regularly undertaken by our security services.
“Any terrorist wishing to destroy the barrier would require a phenomenally high level of technical knowledge, not to mention a shedload of explosives – that’s if they were able to get past the impressive security measures already in place at the site.”
A spokesman for the Environment Agency, which runs and maintains the barrier, said: “We take security very seriously.
“There are robust security measures in place at the barrier and we keep these under constant review.”
Colonel Richard Kemp, who was formerly responsible for critical national infrastructure targets in London, said: “It would be a very difficult thing for terrorists to achieve.
“But such an attack could have a devastating effect on people’s lives and on the economy in general.
“The police and security organisations are well aware of the risk of an attack and they are focused on stopping it happening.”
The £500m barrier was completed in 1982 and spans 520 metres across the Thames near Woolwich, in South-East London.
It protects the capital from flooding caused by regular tidal surges.