Lee Rigby's Killers Had Figured in Inquiries, but Report Calls Response "Inadequate" LONDON - The two men who killed a British soldier last year had figured in seven investigations by British intelligence agencies, and one of the men had threatened to kill a soldier in an online exchange five months before the attack, lawmakers said in a report issued on Tuesday. A parliamentary committee investigating the brutal killing of the soldier, Lee Rigby, in May 2013 pointed to a series of mistakes by the spy agencies that preceded his death, but also blamed an American technology company for failing to report the online threats, which emerged only after the murder. The men, Michael Adebolajo, 29, and Michael Adebowale, 23, were sentenced to life in prison in February for killing Mr. Rigby, who was run over by a car in broad daylight and then stabbed to death in the Woolwich area of southeast London. Mr. Adebowale was ordered to serve a minimum of 45 years. Tuesday's report acknowledged that the two attackers had, between them, appeared in seven different investigations by British agencies, and criticized delays, errors, and the agencies" failure to follow proper procedures and record decisions. Document: Report on the Intelligence Relating to the Murder of Fusilier Lee Rigby Mr. Adebolajo was a high priority for the British intelligence agency MI5 during two investigations, the report said, though intrusive monitoring of him ended about a month before the murder. The investigations revealed no evidence that an attack had been planned, it said. The report also pointed to failings by British intelligence services in monitoring Mr. Adebolajo after his arrest in Kenya in 2010, where he had been detained because it was believed that he was trying to travel to Somalia to join the Shabab militant Islamic group. The response of the British intelligence services was "inadequate," the committee said. The report said Mr. Adebolajo had claimed that during his detention, he was mistreated by Kenyan authorities, beaten and threatened with electrocution and rape. "They failed to investigate his allegations of mistreatment," the report said, adding that the agencies did not grant him "sufficient priority upon his return to the U.K." and did not seem to take the claims seriously. The report concluded, "Given what the agencies knew at the time, they were not in a position to prevent the murder" of Mr. Rigby, who was a fusilier, a type of infantryman. However, the report highlighted an online exchange in December 2012 between Mr. Adebowale and an extremist overseas, in which Mr. Adebowale expressed his intent to kill a soldier. At the time, an American technology company had disabled eight of Mr. Adebowale's accounts because of online comments suggesting terrorist intent. The report did not identify the company. "The party which could have made a difference was the company on whose platform the exchange took place," the report said. However, this company does not appear to regard itself as under any obligation to ensure that its systems identify such exchanges, or to take action or notify the authorities when its communications services appear to be used by terrorists. "There is therefore a risk that, however unintentionally, it provides a safe haven for terrorists to communicate within," it added. The report said none of the major American companies it had approached proactively monitor and review suspicious content on their systems or see themselves as compelled to comply with British warrants. Technology companies, including Apple, Microsoft, Yahoo and Twitter, "need to play their part," Malcolm Rifkind, chairman of the parliamentary intelligence and security committee, said at a news conference after the publication of the report. Mr. Rifkind said he was unable to name the American technology company that had hosted Mr. Adebowale's conversation because information about the exchange had been provided in confidence to British intelligence agencies.