Leslie Johnson walked into the Prince George’s County Council chambers Tuesday morning and began her usual routine — joining her colleagues in prayer and the Pledge of Allegiance. Although most of the council didn’t know it, she had just handed in a resignation letter. Minutes later, she left through a back door.

It was Johnson’s first appearance in public since she pleaded guilty last week to destroying evidence in a federal investigation of county government corruption. At the time, Johnson (D-Mitchellville) said she would stay on the council until her sentencing in October, prompting vociferous objections from fellow politicians and the public. Tuesday’s letter moved the resignation date to July 31.

But Johnson’s unexplained change of heart did not buy her any sympathy. The other council members voted Tuesday to request her immediate departure. The council administrator said he would seize her cellphone, county car, parking pass and computer if she did not turn them over voluntarily.

“We would like Ms. Johnson to tender her resignation immediately,” council Chairman Ingrid Turner (D-Bowie) said after the closed-door meeting.

County Executive Rushern L. Baker III had already sounded an unequivocal call for Johnson’s departure, and after the news Tuesday, he said Johnson should not wait until the end of the month. “The resignation should be as quickly as possible,” Baker (D) told reporters.

Whether she bows to the pressure, Johnson — by moving up her departure — will spare the county additional political acrimony, which was building around her decision. The special election to choose her successor will be held months sooner. And she will forgo thousands of dollars in salary that would have been owed to her had she stayed on until her sentencing in October.

But the situation underscored the lack of teeth in the council’s governance mechanisms — something members have said they hope to change.

“We can continue to urge,” Turner said, noting that the panel has little legal power to force Johnson out of office.

In a written statement Tuesday, Johnson said: “My resignation is important for the constituents of District Six so that the District can be in the best possible position to continue to move forward. I again apologize for my mistake.”

At the council meeting, she said even less. After the pledge, Johnson, 59, was suddenly gone. She left the dais and went out the back door as the council voted to meet in the closed session to discuss her fate.

As several hundred county residents, including Acting Police Chief Mark Magaw, Acting Fire Chief Marc Bashoor and dozens of taxi drivers waited in the crowded council chamber for other items on the agenda, the council voted to go into a closed session.

When the council reemerged, Turner said it had voted unanimously to urge Johnson to resign immediately and would ask her to turn in her county-issued equipment. The council’s administrator, Bobby Williams, said later that the county could seize the items if Johnson did not turn them over voluntarily.

The council also reassigned her staff to report to Williams and will freeze grant funds that she, like every council member, was allowed to hand out to local nonprofit groups.

But as long as she remains on the council, Johnson will continue to draw her salary, which totals about $1,870 a week.

It was clear from Turner’s tone at a late afternoon news conference that the day had marked a turning point in the council’s relationship with Johnson.

“We have not had contact with Ms. Johnson,” said Turner, a political ally and sorority sister of Johnson’s. “We have not seen Ms. Johnson. We have not talked to Ms. Johnson.”

There is little in state or county law that gives the council or county government the tools to push her out.

Tuesday’s events were the latest chapter in a drama that began eight months ago, when she was arrested with $79,600 in cash in her bra and underpants. Other twists include her decision to take office despite her Nov. 12 arrest and her claim outside the courthouse that her actions were a simple “mistake.”

She had been overheard on a federal wiretap with her husband, then-County Executive Jack B. Johnson (D), discussing how to get rid of evidence of bribes from developers. Jack Johnson pleaded guilty last month to taking more than $400,000 in bribes. He will be sentenced in September.

Last week, Baker ended his long silence about Leslie Johnson and called for her to resign immediately. Four other council members — William A. Campos (D-Hyattsville), Mel Franklin (D-Upper Marlboro); Mary A. Lehman (D-Laurel) and Eric Olson (D-College Park) — also said Johnson should step down right away.

Until Turner told her fellow council members in the closed session that Johnson had offered to resign July 31, council members said they had no clue about what Johnson had planned for her return.

Baker, too, was caught by surprise, saying that a staff member had shown him a text message saying a rumor was flying that Johnson would quit.

The cloud cast by the Johnsons continues to hover over Baker’s administration, perpetuating the county’s reputation as a place where businesses must “pay to play,” Baker has said.

“We are a city on a hill,” Baker told the council Tuesday as he was introducing his choices for police chief, fire chief, budget director and finance director, all of whom were approved Tuesday. “The whole world is watching.”

Once Johnson resigns, the county has 45 to 60 days to hold the Republican and Democratic primaries and 60 to 90 days to conduct the special general election. County elections administrator Alisha Alexander said it will cost the county $200,000 to $250,000 to hold the primaries and general election in Johnson’s district, which has about 110,000 residents. Voter turnout in off-season and special elections generally has been low in the county, but this one could be different, depending on when it is held, because of the long spotlight Johnson has been under since her arrest.

Among those eyeing the race are several people who ran against Johnson in last year’s Democratic primary, including Venus Bethea, Derrick Leon Davis and Arthur Turner. Former council member Sam Dean, who had been rumored to be seeking his old seat, said he does not expect to run. “It is not in my plans,” Dean said.

Dean had been barred by term limits — two four year terms — from running last year, which opened the door for Johnson’s victory in the Democratic primary and general election.

Staff writers Ruben Castaneda, Hamil R. Harris and Avis Thomas-Lester contributed to this report.