A Massachusetts man detained under a terrorism probe faces charges in federal court on Wednesday, federal prosecutors said, as local media reported the man and an associate who police shot dead on Tuesday had planned to try to behead a police officer.
Police arrested the man, named as David Wright by a spokeswoman for U.S. Attorney for Massachusetts Carmen Ortiz, in Everett, outside Boston. He is due to face charges at 3:30 p.m., officials said.
Officers working with the Joint Terrorism Task Force had earlier shot and killed Usaamah Abdullah Rahim, who had been under 24-hour surveillance, after police say he confronted them with a knife.
The pair had planned to try to behead a police officer on Tuesday, the Boston Globe reported, citing a law enforcement official briefed on the case. The report could not immediately be confirmed.
Police have offered little detail on why Rahim was being watched or what charges Wright would face.
Michael Steinbach, assistant director of the Federal Bureau of Investigation's counterterrorism division, discussed the investigation at a Congressional hearing on Wednesday but offered few details.
"The investigation is early on, post-event. So there’s not a lot I can say on the intelligence side," Steinbach said. "We know ISIL has put out a message to attack the West, specifically law enforcement, military," referring to Islamic State militants.
Boston Police Commissioner William Evans on Tuesday told reporters only that they considered Rahim "a threat" and that investigators had found information about him that raised a "level of alarm."
Evans said police had approached Rahim in a parking lot to ask him questions and that he responded by drawing a knife and threatening them. Evans, joined by local FBI officials and prosecutors, met on Wednesday with leaders of the Roslindale neighborhood where the shooting occurred to show them video of the incident.
The video, which Evans said showed the officers backing up before opening fire, was not released publicly.
Local prosecutors have opened an investigation into whether the police shooting was justified.
The apparently foiled attack came six months after two New York City police officers were shot dead in their patrol car in an attack intended as retribution for recent police killings of unarmed black men.