Paul and Nancy Pelosi attend a social function in New York in April 2019. Photo: AFP
Paul Pelosi, the husband of US House of Representatives Speaker Nancy Pelosi, is recovering from surgery after being attacked at home by a hammer-wielding intruder.
Pelosi, 82, was left with a fractured skull and serious injuries to his right arm and hands.
The suspect is said to have demanded to see Mrs Pelosi after breaking into the San Francisco home.
The man arrested at the scene, David Depape, 42, will be charged with attempted murder, assault with a deadly weapon, elder abuse, burglary, and several other felony charges, San Francisco police chief William Scott said.
No motive is known.
Mrs Pelosi - who was on the other side of the country in Washington DC at the time of the assault - flew back to see her husband in hospital.
A spokesman for the senior Democrat said Mr Pelosi was attacked in the early hours of Friday morning "by an assailant who acted with force, and threatened his life while demanding to see the Speaker".
He was admitted to Zuckerberg San Francisco General Hospital for an operation and doctors expect a full recovery, said Mrs Pelosi's spokesman, Drew Hammill.
The Democratic speaker of the US House of Representatives, who is second in the constitutional line of succession to the US presidency, was in Washington with her protective detail at the time of the assault, according to the US Capitol police.
Authorities were still investigating a motive for the predawn attack, which was witnessed and interrupted by police officers dispatched to the Pelosi home for an "A-priority well-being check," Scott told reporters.
The intruder shouted, "Where is Nancy?" before attacking her husband, CNN and The Washington Post both reported, citing unnamed sources. CNN said the assailant also told police at the scene that he had been "waiting for Nancy."
Recent posts on several internet sites by a user named "daviddepape" include references to anti-Semitic conspiracy theories, criticism of women, "satanic paedophilia," censorship by tech companies, and other far-right political themes. Older messages promote quartz crystals and hemp bracelets.
Reuters could not confirm that the posts were made by the suspect.
It was unclear how the intruder got into the three-storey red brick townhouse in the affluent Pacific Heights neighbourhood. Aerial photos showed shattered glass on a door at the rear of the house. Streets around the residence were closed off on Friday morning.
The assault occurred less than two weeks before midterm elections in which control of the House and US Senate is at stake.
Scott said police were called to the house at 2.27am local time, where they encountered Depape and Paul Pelosi struggling over a hammer, before Depape pulled the hammer away and attacked Pelosi.
Police officers tackled, disarmed and arrested Depape and took both men to a hospital for treatment, Scott said at a press briefing. He declined to answer questions, and said police would provide more details later.
Several media outlets reported that Paul Pelosi was undergoing brain surgery, while the Associated Press reported that he was being treated for bruising and severe swelling. Reuters was unable to confirm those accounts.
The scene outside the Pelosis' home in San Francisco after the break-in. Photo: AFP
President Joe Biden called Pelosi to express his support, according to White House spokesperson Karine Jean-Pierre.
House Republican Leader Kevin McCarthy also said he reached out to Pelosi, while Senate Republican Leader Mitch McConnell said he was "horrified and disgusted" by the attack.
The Capitol police, responsible for protecting Congress, said officers were working with the FBI and San Francisco police on the investigation.
New York City police warned on Thursday that extremists could target politicians, political events and polling sites ahead of the midterm elections.
Republicans have been campaigning on concerns about violent crime, as well as inflation and other quality-of-life issues. San Francisco's crime rate in 2021 was 1.5 times the national average, according to several crime-tracking websites.
As a Democratic leader in Washington and a longtime representative from one of America's most liberal cities, Pelosi, 82, is a frequent target of Republican criticism and is often featured in attack ads.
Her office was ransacked during the Jan. 6, 2021, attack on the US Capitol by supporters of Republican then-President Donald Trump, some of whom hunted for her during the assault.
In January 2021, her home was vandalized with graffiti messages saying "Cancel rent" and "We want everything" painted on the house and a pig's head left in front of the garage, according to media reports.
McConnell's home also was vandalised around that time.
Representative Adam Kinzinger, one of two Republicans on the House 6 January panel, condemned the rise of incendiary campaign rhetoric vilifying political opponents and promoting falsehoods about widespread voter fraud.
"When you convince people that politicians are rigging elections, drink babies blood, etc, you will get violence. This must be rejected," he wrote on Twitter, calling on Republican candidates and elected officials to "speak out, and now."
In a politically polarised climate, threats against Republican and Democratic lawmakers have been on the rise. Capitol police said they investigated 9625 incidents in 2021, nearly a threefold increase from 2017.
A gunman angered by Trump shot and wounded five Republican members of Congress at a baseball practice in 2017, and Democrat Gabby Giffords was shot in the head at a public appearance in 2011.
Paul Pelosi, who owns a San Francisco-based real estate and venture capital firm, was convicted of a misdemeanour charge of driving under the influence of alcohol after becoming involved in an auto accident in May.
He was sentenced to five days in jail in Napa County, California, but his term was offset by community service and credit given for time already served immediately following his arrest.
- Reuters