Following the attack that targeted the husband of US House Speaker Nancy Pelosi yesterday at their residence in San Francisco, 82-year-old Paul Pelosi reportedly underwent brain surgery.

Pelosi was treated on the scene by police officers who arrived on site after the attack, for injuries in the face, before being transferred to the Zuckerberg San Francisco General Hospital stated KNTV citing an anonymous source. While the reports indicated he was in a stable condition, there is no mention of why doctors found the need to perform the surgery.

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According to the office of House Speaker Nancy Pelosi, her husband is expected to make a full recovery, adding that a joint investigation was launched by the FBI, US Capitol Police and San Francisco Police Department into the attack.

The House Speaker was in Washington when the break-in occurred, US Capitol Police stated.

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Police Chief Bill Scott told reporters that police units were sent to the Pelosi's residence at 2:37 am on a well-being check, where they found the suspect and Paul Pelosi wielding a hammer, adding that the 42-year-old suspect David Depape pulled "the hammer away from Mr. Pelosi, and violently assaulted him with it."

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"Our officers immediately tackled the suspect, disarmed him, took him into custody, requested emergency backup and rendered medical aid," Scott added.

According to police, the suspect is being charged with attempted homicide, assault using a deadly weapon, in addition to burglary and other felonies.

Capitol Police is also sending a special team of investigators from the East Coast to assist the previously sent special agents in the probe.

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White House press secretary Karine Jean-Pierre announced that American President Joe Biden called Pelosi  "to express his support after this horrible attack."

"The president is praying for Paul Pelosi and for Speaker Pelosi’s whole family," Jean-Pierre said, adding that President Biden is "very glad that a full recovery is expected."

"The president continues to condemn all violence and asks that the family’s desire for privacy be respected," said the press secretary.

It's worth noting that the attack comes two weeks before the US midterm elections.