The Redskins weren't the only ones pondering the bad turn of events during the weekend.

Fairfax County police yesterday reported an unusual, unexplained crime wave throughout the county, beginning on Friday and including the vandalizing of 96 cars at a used-car dealership near Falls Church.

"Was it a full moon or what?" asked a puzzled police spokeswoman.

"It was the busiest weekend in the last six months," said officer Connie J. Curran.

"It was such a wide variety of crimes, I really can't find any explanation for it."

Several establishments were targets, she said, in addition to Crossroads Cars, where paint thinner was poured over the entire inventory of used cars and an office and garage were set afire about 10:15 p.m. Saturday, causing an estimated $64,000 in damage.

At Black, Starr and Frost, a jewelry store at Fair Oaks Mall, dia-mond rings worth an estimated $40,500 were stolen, she said.

Curran said a man who identified himself as a doctor went to the store and asked to see some "large carat rings" for his wife.

The jewelry store, which did not have any on hand, brought some in on Friday morning from another store, Curran said.

The man apparently switched them with some fake rings, Curran said.

Later Friday night, Curran said, a Godfather's Pizza restaurant in the Penn Daw area south of Alexandria was robbed.

The next morning, a Hess service station in the Hybla Valley area was hit.

Also Saturday morning, a 17-year-old Falls Church area youth was robbed of his wallet in a field in the Mount Vernon area.

That night, a Chesapeake Bay Seafood House in McLean was robbed.

Also in the Penn Daw area, several cars were found overturned on Sunday morning.

And a robbery occurred at the Springfield Gulf service station that afternoon.

All of the robberies involved small amounts of money, Curran said.

A 15-year-old Dale City youth was arrested Sunday night and charged with auto larceny and burglary.

Early yesterday a 14-year-old Herndon boy was arrested after he allegedly fled from an officer; he was charged with auto theft and assorted traffic violations in the Reston area.

In addition, a 17-year-old Reston girl was injured in a traffic accident during the weekend and individual traffic accidents in Annandale and McLean caused serious injuries, according to police.

At Crossroads Cars, 5719 Leesburg Pike, manager Bill Burnett and his employes were cleaning up the mess yesterday.

"They burned out two buildings," Burnett said, and poured paint thinner on hoods and trunks of the cars on his lot.

Damage to the used cars was estimated at $24,000, police said, and structural damage to the buildings totaled about $40,000.

Authorities said the destruction could have been much worse if a Fairfax County police officer hadn't driven by and seen smoke coming from a window in a trailer. "These are all cheap cars," said Burnett, who said they sell for $600 to $2,000. "It's not like having new cars sitting out there."

Burnett, who was open for business yesterday and grateful to have a telephone and electricity, said he had no idea who was responsible for the crime spree.

"But it was pretty obvious it was some kind of revenge," he said.