A Russian police officer walks along a wall, left, as a British security officer, right, guards the British Embassy building in Moscow on Wednesday, Dec. 6, 2006. Andrei Lugovoi, a key witness in the radiation poisoning case of former Russian agent Alexander Litvinenko, will meet with British investigators on Wednesday, a business associate said. Lugovoi traveled to London three times over the month before Litvinenko's death and met with Litvinenko four times, according to Russian media.
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