Insurers for the developers of a Charles County subdivision that was devastated by arson fires last December have filed a federal civil lawsuit accusing a private security company of negligence and breach of contract for failing to properly screen and train its officers, one of whom has pleaded guilty to helping set the fires.

A second guard formerly employed by the North Carolina-based Security Services of America LLC has been charged with making a false statement in connection with the arson investigation.

The nine-page lawsuit, filed on behalf of the insurance company Axis Specialty Europe Limited and the underwriter Lloyd's of London, alleges that the security company, which was hired to guard the Hunters Brooke development in Indian Head, failed to investigate the backgrounds of its employees.

It also accuses the security company of employing guards it knew or should have known were capable of harming the property they were supposed to protect.

The lawsuit, which was filed last Friday in U.S. District Court in Greenbelt, alleges damages of more than $3 million.

Aaron L. Speed, the former security guard who pleaded guilty last month to conspiracy to commit arson, admitted as part of his plea deal that the financial loss attributable to his conduct was nearly $4.18 million.

A spokesman for Security Services of America did not return phone calls yesterday.

The fires were set in the early morning hours of Dec. 6. The series of blazes, Maryland's biggest residential arson in memory, destroyed 12 unoccupied new houses and damaged 15 others.

When he pleaded guilty on June 23 in U.S. District Court in Greenbelt, Speed, 21, said he was motivated by anger toward the security company and resentment toward the affluent homeowners who were moving into Hunters Brooke.

According to a statement of facts signed by Speed as part of his plea bargain, he helped steal flammable liquids used to start the fires, encouraged a fellow security guard who was on duty that morning to leave early and participated in lighting the fires. Some of the material used by the arsonists was stashed at the subdivision when Speed was on duty several nights before the fires, concealed in drywall buckets and large plastic containers, the statement said.

Before helping set the fires, Speed also drew a map of the subdivision, identifying an occupied house so it would not be targeted, the document stated.

As part of his plea deal, Speed has agreed to cooperate with authorities investigating the fires. Three men remain charged with the arsons; the first trial, that of Patrick S. Walsh, is scheduled to begin Aug. 16. Speed is expected to testify for the government.

A second former Security Services of America guard, William Fitzpatrick, was indicted in March on a charge of making a false statement to investigators probing the fires. Fitzpatrick told investigators that he left his security post at Hunters Brooke at 4:45 a.m. Dec. 6, even though he left earlier, according to the indictment.

In April, one of Speed's codefendants, Jeremy D. Parady, 21, a former volunteer firefighter, pleaded guilty to one count of conspiracy to commit arson. In a statement of facts prosecutors submitted as part of Parady's plea, Parady said he helped target the Hunters Brooke development because he knew or believed many of the people buying homes there were African American. Neither Parady nor any other defendant has been charged with a hate crime.

In 2002, Security Services of America was sued by the mother of a construction worker who was shot to death by a co-worker at a job site in Florida. The lawsuit alleged that the man charged with the killing had a criminal record, which should have been uncovered during a background check.

Staff writer Amit Paley contributed to this report.

Aaron L. Speed, a former security guard, pleaded guilty in the case.