A Fairfax City discotheque arson case was referred to a grand jury yesterday after a witness reported hearing a man urge the defendant to take a walk around the club "before it burns down."

Several hours later, 24-year-old disco patron Hilda Helu told General District Court Judge J. Mason Grove, the Bachelors Two nightclub was destroyed by an early morning blaze.

The judge ordered the case of Manonichem (Manny) Rahnama, president of Bachelors Two Inc., the club's owner, to be considered by the county grand jury, which could return an indictment.

In an affidavit filed before yesterday's preliminary hearing, an unnamed citizen reported seeing Rahnama running from the rear of the disco shortly before the fire was reported March 20. Officials estimated damage from the blaze at $1.2 million.

Testifying yesterday, Fairfax City Fire Marshall Joseph Gebauer reported his investigation turned up nine separate areas in the building at 10960 Lee Hwy. that had been splashed with a petroleum-based substance. Gebauer said the rear door, through which Rahnama was reported to have fled, could be opened only by using a key from inside.

Rahnama's lawyer, Stephen A. Armstrong, argued that the case was a witch hunt "that would more appropriate in old Salem than modern Virginia." Armstrong said his client, a U.S. citizen, was being prosecuted for his Iranian heritage rather than his alleged involvement in the nightclub blaze.

The disco's state license to sell liquor was suspended a week before the blaze, according to testimony of an investigator for the Alcoholic Beverage Control Board. The investigator, Philip G. Disharoon, said Rahnama had also been informed that there was a "good chance" the nightclub would lose its liquor license outright because it appeared to have been selling more liquor than it was reporting to the state.