An Italian, Mario Scaramella who met - ex-KGB agent - Alexander Litvinenko on the day the Russian became ill from radiation poisoning was arrested.
He was arrested on Sunday in Naples while returning from London and taken to Rome, the man's father, Amedeo Scaramella said.
Scaramella, who is the first person connected to the poisoning case to be arrested, met Litvinenko at a London sushi bar Nov. 1, the day the former KGB agent became ill.
Litvinenko died of poisoning from radioactive polonium-210 on Nov. 23.
Sergio Rastrelli, Scaramella's lawyer while speaking in RAI Tg1 TV news said that he was scheduled to be questioned Wednesday.
Scaramella explained that he had showed Litvinenko e-mails on the Nov. 1 meeting from a confidential source identifying the possible killers of Russian investigative journalist Anna Politkovskaya and listing other potential targets for assassination.