CAMBRIDGE, Mass. (AP) _ MIT police filed drug charges against two people Friday in the case of a student who died after inhaling laughing gas from a plastic bag.

Susan Mosher, a Massachusetts Institute of Technology senior, and recent graduate Rene Ruiz, both 22, face charges stemming from drugs found in the dorm room where Richard A. Guy was found dead Tuesday, said MIT Police Chief Anne Glavin.

Guy, a physics major from Mission Viejo, Calif., was asphyxiated as a result of nitrous oxide inhalation. Mosher, a major in brain and cognitive science, and Ruiz lived together in the same East Campus dormitory as Guy.

The complaint filed in court lists charges that include possession with intent to distribute nitrous oxide, hallucinogenic mushrooms, amphetamines and marijuana. The woman and man also face charges of conspiracy, possession of a hypodermic needles and cruelty to animals _ cats _ though police would not further explain the cruelty charge.

``As a result of our investigation, we have been able to shed light on illegal drug use that existed within the living group at East Campus and quite likely beyond,'' Glavin said.

Mosher and Ruiz were ordered to appear in court for arraignment Sept. 10. A message left on their answering machine was not returned.

At a news conference to announce the charges, MIT President Charles M. Vest called Guy's death ``a grim reminder of so many other needless deaths throughout the country, every year, of young people who foolishly involve themselves with drugs.''

Guy's death came two years after the substance-abuse death of another MIT student shocked the campus. In 1997, 18-year-old freshman Scott Krueger died three days after he was found in an alcohol-induced coma on a fraternity floor.

The death prompted MIT officials to require all freshmen to live on campus beginning in the fall of 2001. The fraternity where Krueger was served was also indicted on criminal charges, though the case was never prosecuted because no one from the fraternity appeared in court.

In July, the school revoked the diploma of a man who bought alcohol consumed by Krueger and other pledges.