The FBI said it is targeting a single assailant as it continues to investigate the death of U.S. Capitol police Officer Brian Sicknick, who died from injuries sustained in the Jan. 6 riot.
A federal law enforcement source and another close to the investigation confirmed the news on Saturday.
Sicknick, 42, was injured "while physically engaging with protesters" and returned to his division office, where he collapsed, according to a Capitol police statement. He was taken to the hospital, where he later died on Jan. 7.
Agents have not pinpointed Sicknick's exact cause of injuries, but recently said they suspect it was from a potential spray-type irritant, such as bear spray that he inhaled during the riot. The investigation into Sicknick's death is being treated as an assault.
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