LONDON—British Airways said on Wednesday that "very low traces" of radiation had been found on two of its aircraft by police probing the death of former Russian spy Alexander Litvinenko.
The airline now faces a logistical nightmare tracking down 33,000 passengers who used more than 200 affected flights over the past month, as well as 3,000 staff.
British Airways said three B767 short haul aircraft were taken out of service for forensic examination.
Initial results showed "very low traces of a radioactive substance on board two of the three aircraft".
Litvinenko, a former Russian spy, died last Thursday of radiation poisoning. Significant amounts of radioactive Polonium 210 were found in his body.
From his deathbed, Litvinenko accused Russian President Vladimir Putin of ordering his slow, agonizing death.
The Kremlin denies any involvement but the Litvinenko case has fueled tensions between London and Moscow. Police are treating his death as suspicious.
British Airways faces a huge challenge tracking down passengers who used these three planes on more than 200 flights, starting with a November 3 London Heathrow to Moscow flight -- shortly after Litvinenko fell ill.
"We are looking at around 33,000 passengers on 221 flights over the past four weeks," a BA spokesman told Reuters. "We have set up a special helpline for customers".
The British airline said the three planes would remain out of service until further notice. Two of the planes are at Heathrow Airport and the third is in Moscow and has not been checked yet.
Low Risk to Health
British Airways said it had been advised "the risk to public health is low".
But this could be a major blow to Europe's third largest carrier which is already facing stiff competition from low-cost rivals, high fuel prices and negotiations with staff over plugging its 1.2 billion pound pension black hole.
BA was also forced to cancel hundreds of flights in August after police said they had foiled a plot to blow up transatlantic airliners.
Home Secretary (interior minister) John Reid, who chaired a meeting on Wednesday of the government's COBRA emergency committee, confirmed tests had started on two of the planes and arrangements were being made for the third to be tested.
He will make a statement to parliament on Thursday.
A post mortem will be carried out on Litvinenko on Friday under secure conditions to avoid possible radioactive contamination.
Mario Scaramella, an Italian KGB expert who met Litvinenko the day he became ill, is under British police protection and underwent medical tests. He was not contaminated, his lawyer said on Wednesday.
Scaramella has denied media reports he is viewed as a suspect in the immensely complex case that spans Europe.
Radiation was found at the sushi restaurant where Litvinenko met Scaramella on November 1 and traces have also been detected at several more sites, including Litvinenko's home, a hotel he visited, the offices of Russian tycoon Boris Berezovsky and the offices of Erinys, a security and risk management company.
London police said they were also searching the Sheraton Park Lane Hotel Piccadilly and another London address.
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