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WASHINGTON (FOX 5 DC) - New details are emerging on Friday about the death of a U.S. Capitol police officer who died after an attack on the Capitol building earlier in the week.
Officer Brian Sicknick succumbed to his injuries on Thursday.
According to an EMS report, they were called to a possible cardiac arrest when they found Sicknick "unresponsive" and struggling to breathe.
They believed he suffered a head injury, but also found evidence of "suspected exposure."
FOX 5’s Lindsay Watts reports that the suspected exposure indicates that Sicknick may have been hit by some kind of chemical agent during the incident.
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It has been reported that he was hit with a fire extinguisher.
Capitol police say Sicknick would have been at his office when he collapsed.
Sicknick was one of five people who died during the mayhem on Capitol Hill.
Earlier in the day, thousands had poured into downtown D.C. to listen to President Trump speak.
Shortly after the rally, mobs of Trump supporters stormed the Capitol building, wreaking havoc throughout.
Dozens have been arrested in the wake of the attack.