Fairfax County police have confiscated more than $250,000 worth of marijuana and Quaaludes in one of the largest drug seizures in the county's history.

"We normally don't see these volumes warehoused here," said chief prosecutor Robert F. Horan Jr. "It's a major seizure of drugs."

The drugs allegedly were found when investigators armed with a search warrant went to a home at 2521 Hunter Mill Rd. in Oakton, near Fairfax City.

The raid took place last Wednesday, but details were not disclosed until yesterday.

Two residents of the Oakton home and a Maryland man have been arrested on charges of possessing marjuana with the intent to distribute it. They were identified as John D.. Edeman, 28, an electronics assistant, Frank Matthew Hopewell, 21, a student painter, and Donald Edwin Scott, 27, a student, of Oxon Hill. They were released after each posted $25,000 bond.

Horan said the arrest resulted from an investigation that has been under way for many months. "It arises out of a number of other transactions," he said.

A confidential iformant who has sold drugs in the past helped police make the arrests, according to a police search warrant affidavit filed in the case.

On the day of the raid, according to the affidavit, the informant obtained marijuana at the Oakton address and turned it over to the police.

When police searched the house they found more than 500 pounds of marijuana and more than 1,400 Quaaludes, a strong sedative, according to Horan.

The Quaaludes were found inside a safe, and some marijuana was also uncovered in a 1978 Chevrolet parked outside the house, the affidavit said.

Investigators also seized two knifes, business records and more than $300 in cash, according to court papers.

Police have scheduled a news conference for 2 p.m. today to display some of the drugs and other items seized.

Preliminary hearings for the three men charged are scheduled for Feb. 21 in General District Court.