WASHINGTON (AP) — President Donald Trump's role in inciting violence at the Capitol and his refusal to acknowledge his election defeat is prompting some lawmakers to urge his removal from office through the 25th Amendment.

The amendment allows for the vice president and a majority of the Cabinet to declare a president unfit for office. The vice president then becomes acting president. The section of the amendment specifically addressing this procedure has never been invoked.

On Thursday, a day after a pro-Trump mob stormed the Capitol, the Senate's top Democrat, Chuck Schumer of New York, called for Trump's immediate removal. "What happened at the U.S. Capitol yesterday was an insurrection against the United States, incited by the president. This president should not hold office one day longer," Schumer said.

In remarks posted on Twitter, Rep. Adam Kinzinger, R-Ill., called on the Cabinet to invoke the amendment.

"The president is unfit. And the president is unwell," Kinzinger said. He said Trump "must now relinquish control of the executive branch voluntarily or involuntarily."

Some questions and answers about the 25th Amendment:

WHY WAS IT PASSED?

The push for an amendment detailing presidential succession plans in the event of a president's disability or death followed the assassination of President John F. Kennedy in 1963. President Lyndon B. Johnson in his 1965 State of the Union promised to "propose laws to insure the necessary continuity of leadership should the President become disabled or die." The amendment was passed by Congress that year and ratified in 1967.

HAS THE 25TH AMENDMENT BEEN INVOKED BEFORE?

Yes, presidents have temporarily given up power, but those instances have been generally been brief and voluntary, for example when the president was having a medical procedure.

In 2002, President George W. Bush became the first to use the amendment's Section 3 to temporarily transfer power to Vice President Dick Cheney while Bush was anesthetized for a colonoscopy. Section 4 of the amendment, which allow the Cabinet to declare the president unfit, has never been invoked.

HOW CAN THE CABINET DECLARE THE PRESIDENT UNFIT?

The 25th Amendment's Section 4 lays out what happens if the president becomes unable to discharge his duties but doesn't transfer power to the vice president himself.

The vice president and majority of the Cabinet can declare the president unfit. They then would send a letter to the speaker of the House and president pro tempore of the Senate saying so. The vice president then becomes acting president.

The president can send his own letter saying he is fit to serve. But if the vice president and majority of the Cabinet disagree, they can send another letter to Congress within four days. Congress would then have to vote. The president resumes his duties unless both houses of Congress by a two-thirds vote say the president is not ready.

ISN'T THERE SOME OTHER LEGISLATION ABOUT THIS?

Section 4 of the amendment also gives Congress the power to establish a "body" that can, with the support of the vice president, declare that the president is unable to do the job. If they agree the president is unfit, the vice president would take over. But Congress has never set up the body.

In October, House Speaker Nancy Pelosi, D-Calif., announced legislation that proposed the creation of a commission to fill that role. The legislation would set up a 16-member bipartisan commission chosen by House and Senate leaders. It would include four physicians, four psychiatrists and eight retired public figures such as former presidents, vice presidents and secretaries of state. Those members would then select a 17th member to act as a chair.

After the commission was in place, Congress would be able to pass a resolution requiring the members to examine the president, determine whether the president is incapacitated and report back.