Paul Pelosi, the husband of House Speaker Nancy Pelosi, was "violently assaulted" after a break-in at the couple's California home early on Friday, her office said in a statement.

"The assailant is in custody and the motivation for the attack is under investigation," the statement said. "Mr. Pelosi was taken to the hospital, where he is receiving excellent medical care and is expected to make a full recovery."

The Democratic speaker of the U.S. House of Representatives, who is second in line to the presidency, was not at home at the time of the early morning assault.

The U.S. Capitol Police, FBI & San Francisco Police Department have launched a joint investigation into the break-in and attack, Nancy Pelosi's office said. In addition to the special agents from the Capitol Police's California Field Office who arrived on the scene quickly after the attack, the department is also sending a special team of investigators from the East Coast to aid the probe.

U.S. President Joe Biden called Speaker Pelosi Friday morning "to express his support after this horrible attack," spokeswoman Karine Jean-Pierre said in a statement.

"The president is praying for Paul Pelosi and for Speaker Pelosi's whole family," she said in a statement, noting that 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," added Jean-Pierre.

The assault comes less than two weeks before midterm elections in which control of the House and the Senate is at stake.

Paul Pelosi, 82, who owns a San Francisco-based real estate and venture capital firm, was convicted of a misdemeanor 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.