MOBILE scanners that can detect so-called "dirty bombs" are to be introduced at Scottish ports to counter the increased terrorism threat, The Scotsman has learned.
Operation Cyclamen - a screening programme to prevent radioactive material being brought into the country - comes into force next month, with every customs officer in Scotland to be trained in using radiation scanning equipment.
The first tranche of senior staff is undergoing training as part of the Home Office crackdown, with a wider programme for rank-and-file officers to be rolled out at all ports and airports in the country.
As well as plans for a permanent state-of-the-art radiation scanner at Rosyth port in Fife, mobile radiation detection units will also be moved around Scotland and the north of England to cover the main ports.
But Home Office sources raised concerns last night that Scotland would have too few units to cover its 148 ports and 6,000 miles of coastline, raising the prospect of a terrorist cell striking at a facility without the necessary cover.
"The ports and airports lack cover and they need a permanent customs presence," said the source. "You need 24-hour manning, otherwise there's no point in having this type of equipment."
The Scotsman understands that the mobile units, which cost 350,000 each, will arrive in Scotland at the end of February. There will be three units covering Scotland and the north of England - including Hull and Liverpool - with a total of ten for the whole of the UK. The vans resemble large Land Rovers with trailers, which are driven alongside suspect cargo. Similar to a Geiger counter, the machine detects even tiny amounts of radiation.
The move is part of a 330 million campaign financed by the Home Office, reflecting growing concern that al-Qaeda terrorists are planning a nuclear, biological or chemical attack in Britain.
Last night the Home Office said the measures would form a key plank of anti-terrorist operations in Britain, but for security reasons, refused to confirm exactly where the scanners would be sited.
Frank Campbell, senior national officer with the Public and Commercial Services Union, which represents the UK's 80,000 customs officers, said Operation Cyclamen would only be successful if sufficient staff were put in place.
"The number of places of entry across Scotland's coastline is vast," he said.
"People turn the boat away when they find out there's going to be a crackdown at a particular port. The mobile scanners are a step in the right direction but you need a physical presence to act as a deterrent."
Radioactive detection devices have already been fitted at Waterloo international station and Heathrow and Gatwick airports in England, and the aim is to extend Operation Cyclamen to the rest of the UK.
Dirty bombs - small amounts of toxic or radiological material wrapped inside a large quantity of conventional explosive - are unlikely to cause mass casualties, but could contaminate large urban areas, sparking panic and chaos.
Intelligence chiefs fear an attack using a dirty bomb concealed in a container ship brought into a British port.
A spokesman for HM Revenue and Customs said: "For security reasons, details of the numbers or locations of radiation detection units cannot be disclosed."
• What is a dirty bomb?
A device composed of explosives such as dynamite or Semtex and radioactive materials like plutonium. The bomb blast rapidly disperses the radioactive particles, creating a radioactive contamination hazard. The blast is no more forceful than any other type of high explosive.
Have dirty bombs ever been used by the military?
No, they are considered inappropriate because the effect is unpredictable.
Why would terrorists use a dirty bomb?
Fear and intimidation are key aspects of the threat of the dirty bomb. The anthrax attacks in the US in 2001 outlined just how effective biological attacks can be as weapons of terrorism.
To what extent are dirty bombs economic weapons?
Decontamination costs and the long-term health costs could run into millions of pounds and would also hit trade and tourism.