The man suspected of setting fires to dozens of houses and apartments in the Washington region is scheduled to plead guilty Monday to federal charges, according to court papers filed by prosecutors.

Thomas A. Sweatt is to appear in U.S. District Court in Greenbelt, where prosecutors charged him with arson and other felonies in a six-count criminal information that was filed under seal last month. The charging document was made public this week at the request of prosecutors, who filed court papers revealing an apparent plea agreement.

"Since the guilty-plea hearing has now been scheduled . . . there is no longer a need to keep the criminal information sealed, since there is no longer any uncertainty about whether the defendant will be pleading guilty," the prosecutors said in the court filing.

U.S. District Judge Deborah K. Chasanow agreed to unseal the charging papers, along with the prosecution's court papers, in an order issued this week.

Federal prosecutors in Maryland would not comment yesterday. Sweatt also could face charges in the District and Virginia, and authorities declined to say whether they were working toward a plea agreement that would cover all the alleged offenses and jurisdictions.

Assistant Public Defender John C. Chamble, Sweatt's attorney, did not respond to a phone message left at his office yesterday.

Sweatt, 50, has been jailed since his April 26 arrest. At a previous court hearing, prosecutors said he had admitted setting 37 residential blazes over two years, including one that killed an elderly woman in the District. They quoted Sweatt as saying he was addicted to setting fires. Other officials said he spoke to investigators about demons.

Prosecutors can file a criminal information only with the defendant's consent. In Sweatt's case, the filing means he has waived his right to a grand jury in federal court in Maryland, which would have independently weighed the government's case before deciding whether to indict him. The filing of a criminal information often signals a defendant's intention to plead guilty and aid prosecutors.

The criminal information was filed May 19 and charges Sweatt with arson and possessing and using a destructive device.

Sweatt, a fast-food restaurant manager who lived in an apartment in Southeast Washington, has told authorities that he often targeted places that he knew would be occupied. Many of the fires were set late at night or in the early morning, and many were near the Northeast Washington restaurant where he worked or near his apartment.

Plastic jugs filled with gasoline were ignited, often just outside doors or on porches of homes or apartment buildings. Investigators say they believe it took up to 25 minutes for the firebombs to explode. Prosecutors said DNA evidence led to Sweatt's arrest and tied him to several fires.

Channing Phillips, a spokesman for the U.S. attorney's office in Washington, would not comment yesterday when asked if Sweatt will face charges in the June 2003 fire that killed Lou Edna Jones, 86, in her Northeast Washington home. Authorities said that more than a dozen people were injured in the other fires, which caused millions of dollars in damage.

Staff writer Henri E. Cauvin contributed to this report.