Federal investigators found last week that the whistle in the Conrail engine had been deliberately disabled, and they are trying to determine who did that and when.

He said that his staff had corrected all administrative and curriculum problems that state investigators found in preliminary inquiries that began in 1984.

Federal officials then conducted four audits that involved increasingly larger samples in which the investigators found from 5 to 10 percent of the patient cases had data irregularities.

Preliminary tests on the letter, which investigators found on Friday night in a barrel of quarantined mail, showed that it contained anthrax.

Further, investigators found in court and investigative files earlier this week that the boy had been known to hang out with a former soldier named John Allen Muhammad, also known as John Williams, law-enforcement officials said.

Nor have investigators found any local terrorist cells there.

I've been thumbing through the book the investigators found on his nightstand, but so far," she paused, examining the spine of the novel and reading aloud, "The Invisible Man hasn't proved to be much help.

Police have also searched a second house occupied by lacrosse team members, but documents describing the location or what investigators found have been sealed by court order, prosecutors and the police said.

Instead, the investigators found in their preliminary inquiry, the Conrail engineer, proceeded into the convergence point at speeds estimated at 60 miles an hour or more.