Hunt for 'dirty' bombs is stepped up with new passenger scanners

The measures reflect a growing concern that the al-Qa'ida network might be planning a nuclear, biological or chemical attack in this country. Anti-terrorist officers have investigated two plots in the UK involving alleged plans for a chemical or radiological attack since the 11 September 2001 attacks.

The Home Office and the Metropolitan Police have been trialling a series of initiatives to stop a chemical, biological or radioactive attack, and deal with the aftermath of any such terrorist incident, a new report details. Radioactive detection devices have already been fitted at Waterloo international station and Heathrow and Gatwick airports, and all major ports of entry are having similar systems deployed. The Metropolitan Police are trialling a vehicle that contains a machine to detect radioactive material and a "walk-through" scanner.

Ten further vehicles - known as mobile radiation detection units - to take part in stop-and-search and anti-terrorist operations are planned for other parts of the country.

In London the Met intends to fit patrol officers with "escape hoods" that allow them to breathe safely if they come under a radiological, biological or chemical attack. They also have a people carrier that is for "extracting" what the Met calls "significant important persons", such as politicians, police chiefs, and medical specialists, from radiological, chemical or biological attacks, and then decontaminating them.

Details of the measures, which are part of Operation Cyclamen, are disclosed in a report by Commander Mick Messenger, the officer in charge of the forces response to chemical biological, radiological and nuclear (CBRN) incidents. It is being presented to the police authority in London tomorrow.

Commander Messenger's report says: "The MPS [Metropolitan Police Service] will be involved in trials of the mobile radiological detection capability and use of a pedestrian portal.

"Radiological detection has been/is being installed in major ports and transport hubs. Waterloo international station and Heathrow airport have fixed detection capabilities."

He adds: "Since '9/11' the Metropolitan Police Service has been developing an operational response to a deliberate release of a chemical, biological or radioactive material."

The senior officer discloses that the Met is examining plans to have specialist CBRN teams that can be deployed with firearms officers and surveillance units to check for traces of contamination or radioactivity around a terrorist hideout.

The report says: "Officers are also equipped with a range of Home Office approved specialist equipment to assess the release of powder, liquid or vapour.

"In addition, the MPS has taken delivery of five purpose-built CBRN vehicles, including one specially designed for the extraction and decontamination of significant important persons."

A Home Office spokesman said: "Programme Cyclamen is a key part of the Government's counterterrorism strategy, using radiation detection equipment to detect the illicit importation of radioactive materials into the UK by screening inbound passengers, goods and vehicles. Fixed equipment has already been successfully installed at UK ports and is becoming part of the entry checks for people, goods and vehicles entering the UK." The availability of radioactive material was highlighted in November 2004 when a nuclear scientist in Siberia handed over eight containers of weapons-grade plutonium to police after keeping them in his garage for at least six years.

Leonid Grigorov told police that he had found the 400g of plutonium-238 in a pile of rubbish at the laboratory of the mining and enrichment plant where he used to work as a nuclear engineer.