A Rockville abortion clinic was hit by early morning arsonists yesterday, who set several fires in the clinic's first floor offices, destroyed medical records and stole $1,000 worth of medication, Montgomery County fire officials reported.

The vandalism, which fire officials said would close the Sigma Reproductive Health Center indefinitely, came on the eve of a major anti-abortion demonstration against the Rockville center's sister clinic in Fairfax County.

I'd be shocked to think there's any connection at all," said Frank McInerny, spokesman for Roman Catholic Archbishop Thomas Welsch of Arlington, one of the organizers of today's demonstration. "Sometimes coincidences do occur."

The organizers say they expect 500 demonstrators.

The staff of the Rockville clinic was tight-lipped yesterday about the damages and refused to speak to a reporter.

They're afraid for their lives," said an official of the sister clinic, Northern Virginia Women's Medical Center. "Everyone's taking a low profile."

The official asked not be identified.

The Fairfax facility, under the same ownership as the Rockville clinic, has been the scene of protests, arrests and sit-ins by anti-abortion groups including the "Fairfax Eleven."

The 11 were demonstrators banned from the Fairfax clinic last year by a federal judge after the clinic filed suit against the protesters.

"Our windows have been broken; we get harassing telephone calls; our lounge was ransacked, and in May someone broke in and left a 14-week fetus in one of the sinks," the official.

On Aug. 11, the clinic reported receiving three bomb threats.

Yesterday's damage to the Rockville clinic was the most serious act of vandalism in an escalating campaign against Washington area abortion clinics.

"They (the protestors) are making a moral issue into a political issue," said one clinic employe yesterday. "It's getting frightening."

The Sigma Reproductive Center opened in 1974 at 11119 Rockville Pike. Five persons were convicted of trespassing after a nonviolent sit-in at the clinic there last year. It had become a target of frequent anti abortion demonstrations.

A week ago, the clinic moved to its new headquarters at 3937-3941 Ferrara Drive, where the destruction took place.

According to Lt. Carvel Harding of the Montgomery County fire marshal's office, the fire broke out at 6:48 a.m.

"It was definitely arson," he said. "Multiple fires were willfully and maliciously set."

Although none of the medical equipment was damaged Harding said, medical records were destroyed and approximately $1,000 worth of medicine was stolen. Asked if the arson or arsonists intended to close down the clinic,

Asked if the arson or arsonists intended to close down the clinic, Harding said, "Anytime you get $2,500 worth of damage in a medical clinic, with the smoke and everything in a sterile atmosphere . . . that can put you out of business."

The for-profit clinic operated by a physician, nurse and psychologist, performs abortions on women, vasectomies to sterlize men and offers birth control counseling and veneral disease testing.

Fire department officials said late yesterday they had no suspects.

According to a member of the Northern Virginia Women's Medical Center, medical records at the abortion clinics are crucial in the event of post-abortion complications.

The records include information about the type of pregnancy, when it was terminated, what drugs were administered, the vital signs of the patient and other factors which could be crucial in any further treatment of the patient, the staff member said.

Drugs generally kept at the clinic include prescription pain-killers such as Darvon and Demerol and the tranquilizer Valium.

The demonstration against the Fairfax Clinic was planned as a peaceful protest, organizer said. But one staffer said a private security guard had been hired to stand watch last night. Fairfax police are also scheduled to be on hand for the demonstration.