The Capitol police officer who died from injuries suffered during the response to the attack on the  building on Wednesday was a South River native.

The U.S. Capitol Police said in a statement that Officer Brian D. Sicknick was injured “while physically engaging with protesters" during the Wednesday riot. He is the fifth person to die because of the violence fomented after a pro-Trump demonstration.

During the melee, Sicknick was hit in the head with a fire extinguisher, two law enforcement officials said. The officials could not discuss the ongoing investigation publicly and spoke to The Associated Press on condition of anonymity.

Sicknick joined the USCP in July 2008, and most recently served in the department’s First Responder’s Unit.

He did not serve with police in South River but Mayor John Krenzel said the borough was mourning his loss.

“The South River family has been wounded. We share the Sicknick family’s loss and we will keep Brian and his family in our thoughts and prayers,” Krenzel said Friday in a written statement.

“The United States needs to end the insanity that has gripped this nation. We need unity within the new administration,” he added. “It is my fervent wish that the nation returns to its ideals so that we resolve our disagreements and grievances not using violence, but instead with sound discourse and reason.”

According to Middlesex County Commissioner Director Ronald Rios Sicknick was a 1997 graduate of Middlesex County Vocational Technical High School in East Brunswick. He also served with the New Jersey Air National Guard.

"We are saddened by the loss of one of our former New Jersey National Guard Citizen-Airman, Staff Sgt Brian D. Sicknick," New Jersey National Guard public affairs officer Lt. Col. Barbara Brown told New Jersey 101.5. "His commitment to service and protect his community, state, and nation will never be forgotten.

Brown said Staff Sgt. Sicknick enlisted in 1997 as a traditional drilling Guard member and served as a Fire Team Member and Leader at the 108th Security Force Squadron, 108th Wing, located at Joint Base McGuire-Dix-Lakehurst. He deployed to Saudi Arabia in 1999 in support of Operation Southern Watch and to Kyrgyzstan in 2003 in support of Operation Enduring Freedom and was honorably discharged in 2003.

Gov. Phil Murphy and wife Tammy sent condolences to Sicknick's familiy, his fellow Guardsmen and Guardswomen and Capitol police.

“Officer Sicknick gave his life protecting the United States Capitol, and by extension, our very democracy, from violent insurrection. His needless murder at the hands of a mob bent on overthrowing the Constitution he had dedicated his life to upholding is shocking. It is my fervent hope that the rioters whose actions directly contributed to his death are quickly identified and brought to justice," Murphy said.

House Speaker Nancy Pelosi ordered flags to fly at half-staff in Sicknick's honor on Friday.

In a statement to ABC News, his brother said Sicknick was the youngest of three and died a hero.

"I would like to thank all of his brothers and sisters in law enforcement for the incredible compassion and support they have shown my family," he added.

Michael Symons contributed to this report

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Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com or via Twitter @DanAlexanderNJ

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