The husband of US House of Representatives Speaker, Nancy Pelosi, has been “violently assaulted” after a break-in at their California home.
Paul Pelosi, 82, was taken to hospital and is expected to make a full recovery, a spokesperson said.
The suspect, who has not been named, is in custody, but the motive for the attack is unclear.
They reportedly entered the home with a hammer and – after confronting Mr Pelosi – shouted “where is Nancy?”.
Mrs Pelosi was in Washington, and not at the San Francisco residence, when the incident took place on Friday morning.
“The Speaker and her family are grateful to the first responders and medical professionals involved, and request privacy at this time,” a spokesman for the senior Democrat said.
Mrs Pelosi is one of the most powerful politicians in the country. She was re-elected to a fourth term as Speaker of the House of Representatives in 2021, making her second in line to the presidency after Vice-President Kamala Harris.
The Baltimore native has represented the San Francisco area in Congress since 1987, and typically splits her time between California and Washington.
She is currently fundraising and campaigning with Democrats around the country ahead of the midterm elections on 8 November, and was in Washington with her security detail at the time of the attack.
Her husband, the multimillionaire founder of a venture capital firm, resides primarily in San Francisco where he was born and raised.
The couple has been married since 1963 and have five children. Their combined net worth, primarily from Mr Pelosi’s investments, has made the speaker one of the richest members of Congress.
The exact circumstances of the attack are unclear and it is not known how the intruder entered the couple’s residence.
The FBI and the US Capitol Police, which has a field office in California, are assisting San Francisco police with the investigation.
Capitol Police is said to be considering additional protection for the families of congressional leaders.
Members of Congress have been on high-alert over security threats since the riot at the US Capitol in January 2021. Mrs Pelosi’s office in the building was ransacked by supporters of then-President Donald Trump during the attack.
And last year, her San Francisco home was reportedly vandalised with graffiti saying “cancel rent”.
Senior Republicans, such as Senate Leader Mitch McConnell, have also been targeted by vandalism in recent times and politicians have raised concerns about an increase in threats.
Mr McConnell tweeted Friday that he was “horrified and disgusted” by the attack on Mr Pelosi.
In a statement, the White House said President Joe Biden was “praying for Paul Pelosi and for Speaker Pelosi’s whole family”.
Chuck Schumer, the top Democrat in the Senate, said: “What happened to Paul Pelosi was a dastardly act. I wish him a speedy recovery.”
Both added that they had spoken to Mrs Pelosi since the incident.
Earlier this year, Mr Pelosi was convicted of driving under the influence of alcohol and causing injury after he crashed his car. The financier pleaded guilty in August, and was sentenced to five days in jail.