U.S. attorney Ronald C. Machen Jr., the District’s top prosecutor, said he is temporarily leaving the city and returning to his Silver Spring home because the lease on his D.C. residence was not renewed.

Machen, whose investigation of D.C. public officials has led to the resignations of two council members and guilty pleas from several people, including three associates of Mayor Vincent C. Gray (D), has said he has no plans to resign or to cede work.

Federal law requires U.S. attorneys to live in the districts for which they are appointed. But the District, and New York’s southern and eastern districts, are exceptions. A U.S. attorney in those jurisdictions can live within 20 miles of the district.

Several of Machen’s predecessors lived outside the city, but “it’s something I wanted to change,” Machen said.

Machen, a married father of three children, generally has been reticent to discuss his personal life, but he said he did not want people to jump to conclusions about his change in residence.

Rumors swirled last year that Machen was resigning and returning to private practice. He was a partner at WilmerHale when he was named to his post in 2010. “My work is not done,” he said in an interview Thursday. “The work we’re doing here is too important to abandon.”

Machen relocated his family into a rented home in the District after he was selected to the job. But the owners of the home are returning, and his Silver Spring home is “underwater,” Machen said.

Public records show that the amount the Machens paid to buy the property and build the home is nearly $400,000 more than the assessed value.

He said he and his family wrestled with the decision to leave the District. “It’s been a tough time. . . . I’m hopeful that people understand my commitment to D.C.

“This is really something that a lot of families have gotten caught up in,” Machen added, referring to the housing crisis that has left a number of area residents with upside-down mortgages.

Attorney General Eric H. Holder Jr. was supportive of Machen’s decision to move. He said in a statement that Machen “has demonstrated a deep commitment to the people of the District of Columbia through his tireless efforts to engage our underserved communities, reduce violent crime, and fight public corruption. . . . As someone who has called the District of Columbia home for more than three decades, I am confident that U.S. Attorney Machen will remain a valued partner and an engaged leader who will serve our city with vigor and independence.”

Although the family is moving, its two youngest children, who are school age, will remain in D.C. public schools. Machen said he will pay out-of-state tuition. “This is something that’s temporary while we look for a solution,” he said.

The Rev. C. Matthew Hudson, a member of the nominating commission that selected Machen, said he did not have a problem with the move. “I don’t think it will affect what he does for the city,” Hudson said.

Hudson said he had challenged Machen during the interview process about whether he would “make a committment to become involved in the community, particularly east of the river.”

“He kept his commitment,” Hudson said, pointing to a series of town-hall-style meetings Machen held to explain the mission and operations of the U.S. attorney’s office to the public. “He could have sent anybody to represent the U.S. attorney’s office, but he comes himself and interacts with the community.”

Holder noted in his statement that Machen’s work stretches beyond the District. “Machen is currently leading several national security investigations of great significance to the entire country,” Holder said.

In June, Holder named Machen to a team of attorneys leading the probe into the possible leak of classified information to media by the White House.

In the interview Thursday, Machen listed that investigation and the probes into city corruption among the cases that he has no plans to leave unfinished.