Suburban police officials said yesterday they sometimes have to overlook small drug deals and temporarily drop other police investigations because they are so overwhelmed by record volumes of illegal drug sales.

Vast quantities of drugs -- especially cocaine and crack -- from New York and Miami are being bought and sold in Maryland and Virginia neighborhoods, police said. In every jurisdiction around the Capital Beltway, the number of drug-related arrests and the amount of drugs seized increased from 1986 to 1987, sometimes nearly three-fold.

"It's probably the worst dilemma that has hit law enforcement in years," said Prince George's County police Lt. Clark Price. "The dilemma for all law enforcers now is: Do you allow open air markets to flourish {where small quantities of drugs are exchanged} and go after the supplier? What do you do?"

"The problem has come so quickly that it will take local departments time to come up with the resources and manpower to deal with it," said Fairfax County police Capt. William Edmonston.

To combat the surge in illegal drug activity -- Montgomery County police confiscated $6.9 million worth of drugs in 1987, almost three times the year before, and Fairfax County police doubled their drug seizures last year -- suburban police departments have refocused efforts and reassigned officers.

Montgomery has added "jump-out" squads -- officers wearing street clothes and using unmarked cars who make on-the-spot arrests after observing drug sales. This week it also provided a police unit with motorscooters to negotiate alleys and traffic-clogged areas.

Fairfax has put special drug enforcement teams in each of its seven district stations, added officers to drug patrols, and stepped up educational efforts in schools and neighborhood groups.

In Arlington, two special task forces have targeted the Arna Valley and Green Valley areas, where a dramatic increase in street sales have taken place. In one recent sweep of Arna Valley, 130 arrests were made, said Lt. John Karinshak.

Alexandria police, who also use a "jump-out" squad, have assigned every vice investigator, even those working on gambling and prostitution investigations, to drug cases. Lt. Al Levesque, commander of the vice narcotics units, said their major effort has been eradicating street sales in the Charles Houston and Arlandria sections of the city.

In Prince George's County, a special strike force consisting of 43 officers, sheriff deputies and Park Police officers hit the streets on Tuesday. It will saturate more than a dozen apartment complexes that are known for high-volume drug sales.

Police say drugs aren't confined to certain areas or types of consumers.

In the 1970s, Levesque said, the Alexandria department could "bust the top six dealers in the city and not have to worry about the drug problem for a while." Now, he said, "You bust six for cocaine, and there are 150 to take their place.

"Who is buying it?" Levesque said. "They are young. They are in their twenties, thirties and forties. And they are black, white and Hispanic."

Political leaders said they will discuss ways to curb the flow of drugs, a problem about which citizen groups are increasingly vocal. "I'm going to be talking to the board and Jay {County Executive J. Hamilton Lambert} about it to see if our efforts are sufficient," said Fairfax County Board Chairman Audrey Moore.

Montgomery County Executive Sidney Kramer said the drug problem had been given high priority: "We are aware of it and we are putting considerable resources into dealing with it."

"Cocaine has become so prevalent that we have had to raise our sights," Karinshak said. "We haveto . . . go after the big dealers."

Arlington's drug-related arrests reflect the focus on dealers. In 1986 there were 64 arrests for drug distribution; in 1987, the distribution arrests soared to 191.

Staff writer Caryle Murphy contributed to this report.