U.S. Capitol Police (USCP) officer Brian Sicknick has died from injuries he sustained while responding to the siege on the Capitol by a mob of President Trump supporters, the department said in a statement late Thursday.

The big picture: The officer's death is the fifth confirmed death stemming from the riot. A Capitol Police officer shot and killed Ashli Babbitt inside the Capitol, one woman died after being crushed during the breach, and two men died because of "medical emergencies," D.C. police said earlier on Thursday.

• Authorities have said that more than 50 officers reported injuries following Wednesday's riot.

What they're saying: "Officer Sicknick was responding to the riots on Wednesday, January 6, 2021, at the U.S. Capitol and was injured while physically engaging with protesters," USCP said in a statement.

• "He returned to his division office and collapsed.  He was taken to a local hospital where he succumbed to his injuries," the statement added.
• USCP asked for privacy for Sicknick's family and said his death will be investigated by the D.C. Metropolitan Police Department’s Homicide Branch, the USCP and other federal partner agencies.

Worth noting: Capitol Police chief Steven Sund will resign next week after pressure from lawmakers, including House Speaker Nancy Pelosi, and the union representing the Capitol Police over the department's response to Wednesday's violent Capitol breach.