PresidentDonald Trumphas ordered the American flag to be flown at half-staff in honor of Capitol Police, four days after the violent riot that resulted in the deaths of two officers.

On Sunday, Trump, 74, issued a proclamation that called for the flag to be lowered at the White House and all public buildings until Wednesday “as a sign of respect for the service and sacrifice of United States Capitol Police OfficersBrian D. SicknickandHoward Liebengood, and all Capitol Police Officers and law enforcement across this great Nation.”

Sicknick, 42, died Thursday night from injuries he sustained “while physically engaging with protesters” at the riots, United States Capitol Police said in astatement. A colleague, who did not wish to be identified, told PEOPLE he was “agreat guy to work with.”

“You knew you could count on him to do his job and be right there when you needed him. He believed in this country and he believed in all of us [who worked with him],” they said.

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An American flag flies at half-staff above the White House in Washington

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The USCP confirmed the death of Liebengood, 51, an off-duty officer and 15-year veteran who responded to Wednesday’s violent riots, via astatementon Sunday morning. A cause of death was not immediately disclosed.

According to the USCP union, Liebengood, who joined the law enforcement agency in 2005 and was assigned to the Senate Division, “was among the officers who responded to the rioting at the U.S. Capitol on January 6th.”

“We extend our deepest sympathies to Officer Liebengood’s family and we mourn the death of a friend and colleague who worked alongside us to protect the lives of the Members of Congress, their staff and all who serve at the U.S. Capitol,” the union’sstatementread.

According to the Capitol Police, more than 50 officers from the department and Metropolitan Police Department sustained injuries, while several required hospitalization.

“The violent attack on the U.S. Capitol was unlike any I have ever experienced in my 30 years in law enforcement here in Washington, D.C.,” USCP Chief Steven Sund, who resigned from his post on Thursday, said in a previous statement. “Make no mistake – these mass riots were not First Amendment activities; they were criminal riotous behavior.”

source: people.com