'Our loss of will leave a large hole in our hearts': Family of Capitol Police officer Brian Sicknick who died after being struck by a fire extinguisher says he was a 'lovely, humble soul' who 'loved his job' amid federal murder probe

The family of Capitol Police Officer Brian Sicknick released a heartbreaking statement remembering him as a 'lovely, humble soul' on Monday

The family of slain Capitol Police Officer Brian Sicknick released a heartbreaking statement remembering him as a 'lovely, humble soul' on Monday as federal authorities continued their murder investigation.

Sicknick was killed when he was hit in the head by a fire extinguisher during the MAGA riot last week. 

In the statement, obtained by NBC News, the family wrote: 'There really aren’t enough kind words in any language to describe how sweet Brian was. He was truly a lovely, humble soul. We are missing him terribly.

'He was sweet natured through and through. Everyone who met him adored him. He also loved his dachshunds dearly, spoiling them, and ensuring they got the best care possible.'

Sicknick's family said he 'loved his job with the US Capitol Police, and was very passionate about it'. 

'He also had an incredible work ethic. He was very serious about showing up to work on time and refused to call out sick unless absolutely necessary.

'Our loss of Brian will leave a large hole in our hearts. The tremendous support we have received from the US Capitol Police, the law enforcement community, and the community as a whole has been overwhelmingly warm and generous. We’re very grateful for everyone’s kindness during this difficult time,' the family added.  

Following his death, the US attorney's office in Washington opened a federal murder investigation. 

The FBI and the DC Metropolitan Police Department are jointly investigating Sicknick's murder with cooperation from Capitol Police. 

In a statement, Acting Attorney General Jeffrey Rosen said the Department of Justice 'will spare no resources in investigating and holding accountable those responsible'. 

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In the statement, obtained by NBC News, the family wrote: 'There really aren’t enough kind words in any language to describe how sweet Brian was. We are missing him terribly'

From his early days growing up in a New Jersey hamlet, Sicknick wanted to be a police officer. He enlisted in the National Guard six months after graduating high school in 1997

From his early days growing up in a New Jersey hamlet, Sicknick wanted to be a police officer. 

He enlisted in the National Guard six months after graduating high school in 1997, deploying to Saudi Arabia and then Kyrgyzstan. Joining the Guard was his means to joining law enforcement, his family said.

Sicknick would join the Capitol Police in 2008, serving until his death Thursday after being attacked as rioters seething over Donald Trump's election loss stormed the building, believing the president's false claims of a rigged election. 

'His brother told me, "Brian did his job," said John Krenzel, the mayor of Sicknick's hometown of South River, New Jersey. 

Sicknick's death has shaken America as it grapples with how an armed mob could storm the halls of the US Capitol as the presidential election results were being certified, sending hundreds of lawmakers, staff and journalists fleeing for safety. 

Videos published online show vastly outnumbered Capitol Police officers trying in vain to stop surging rioters, though other videos show officers not moving to stop rioters in the building.

Police leadership badly miscalculated the threat despite weeks of signals that Wednesday could get violent. 

And they refused Pentagon help three days before the riot, and again as the mob descended. 

Under withering criticism, the police chief resigned as have the chief security officers for both the US House and Senate.

The Capitol Police said in a statement that Sicknick was injured 'while physically engaging with protesters'.

During the struggle, Sicknick, 42, 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.

Rep Elissa Slotkin, D-Mich, says she has asked Chairman of the Joint Chiefs of Staff Gen Mark Milley, Army Secretary Ryan McCarthy and Air Force Chief of Staff Gen Charles Q. Brown Jr that Sicknick be buried with posthumous honors at Arlington National Cemetery.

Videos published online show vastly outnumbered Capitol Police officers trying in vain to stop surging rioters, though other videos show officers not moving to stop rioters in the building 

In one video a rioter is seen hurling a fire extinguisher at the head of police officers in the crowd, but it's unclear if this is when Sicknick was fatally injured 

The Capitol Police said in a statement that Sicknick was injured 'while physically engaging with protesters'

'Officer Sicknick died in the line of duty as a US Capitol Police Officer but did so living up to the oath he swore in the military: to protect and defend the Constitution,' she said in her request. She got an encouraging early response from the Army.

'The Office of the Secretary of the Army has received requests on behalf of US Capitol Police Officer Brian D. Sicknick, a veteran, and fully supports the request for posthumous special honors and burial at Arlington National Cemetery, ' said the official who asked to remain anonymous to discuss internal deliberations.

Sicknick was the youngest of three boys growing up in South River, a small borough of about 16,000 people in central New Jersey, 20 miles from Staten Island. 

He graduated from the Middlesex County Vocational and Technical School in East Brunswick, New Jersey, in June 1997. Superintendent Dianne Veilleux said school records show Sicknick wanted to be in law enforcement. The school will honor him by planting an oak tree on campus to symbolize his strength.

He enlisted in the New Jersey Air National Guard that December, still a teenager, first deploying to Saudi Arabia in 1999. 

In 2003, he deployed to Kyrgyzstan, where the US military operated a transit base supporting the war in Afghanistan. He was honorably discharged in December of that year.

In a statement issued Friday, Sicknick's family said he 'wanted to be a police officer his entire life' and had joined the Guard 'as a means to that end'.

A biography issued by his family says Sicknick rooted for the New Jersey Devils hockey team in his spare time. 

He is survived by his parents, Charles and Gladys Sicknick, his brothers Ken and Craig, and his longtime girlfriend, Sandra Garza.

The family asked the public to respect its wishes 'in not making Brian's passing a political issue'.

'Brian is a hero and that is what we would like people to remember,' the family said.

On Saturday, New Jersey Gov Phil Murphy ordered that the US and New Jersey flags be flown at half-staff at all state buildings and facilities in honor of Sicknick, saying he 'embodied the selfless spirit of his native state'.

'Officer Sicknick gave his life protecting the United States Capitol, and by extension, our very democracy, from violent insurrection,' Murphy said. 

'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.'