Twenty people, including two Washington area lawyers, have been indicted in Alexandria in a crackdown on what federal prosecutors called one of the area's largest drug smuggling rings.

The operation allegedly funneled 130 tons of South American hashish and marijuana worth an estimated $75 million into the area during a nine-year period.

Many of those named in the 38-count indictment made public yesterday were said to be either jailed on other charges or fugitives in Costa Rica or elsewhere.

The two lawyers who were accused of helping the ring launder its $30 million in profits and two others were arrested Tuesday night and given hearings yesterday before U.S. magistrates in Alexandria and the District of Columbia.

Lawyer W. Stephen McConnell of Annandale, a former tax attorney with the Justice Department, was charged with smuggling laundered profits through fictitious corporations. He was freed under a $5,000 bond.

Washington lawyer Arthur S. Meisnere, charged with laundering money as well as assisting in the acquisition of boats and aircraft allegedly used for the smuggling, was released after posting an unsecured bond of $250,000. Neither man could be reached yesterday for comment.

The indictment charges the defendants, some of them known by aliases of "Fat Man," "Ice Cream," "Nerves," "Doc" and others, set up an elaborate operation that used boats and aircraft to ferry drugs though the Caribbean to the Tysons Corner area of Northern Virginia. Profits, according to the indictment, were invested in Mercedes-Benz automobiles, property on a South Carolina resort island, more than $800,000 worth of glassware, antiques and Tiffany lamps, stocks and certificates of deposit, as well as investment in numerous legitimate business ventures in the U.S. and abroad.

Part of the alleged scheme was the establishment of numerous fictitious business fronts for the purpose of evading U.S. taxes. Assistant U.S. Attorney Karen Tandy characterized the two-year investigation by the Drug Enforcement Administration and the Internal Revenue Service as one of the largest the government has conducted in the area.

The indictment charges all but three of the 20 defendants with racketeering, a broad charge that includes obstruction of justice, narcotics trafficking, interstate and foreign travel in the interest of racketeering, as well as using fictitious names and laundering profits through law firm escrow accounts and foreign financial institutions.

In addition, three of the defendants, Barry Toombs, Julian Pernell and Leon D. Harvey, were charged with masterminding and managing the drug operation and investing the profits into numerous legitimate businesses. Harvey, described as a fugitive, has been convicted twice previously on drug charges, once in Alexandria and once in South Carolina. In the Alexandria case, Harvey was found guilty of investing drug profits in numerous legitimate businesses, including a Texas shrimp boat operation, a produce business, a motel and a farm in West Virginia where drugs were stored.

Toombs, Pernell and McConnell also are charged in a separate racketeering count with investing $1.8 million in Long Cove Club Associates, a South Carolina development concern.

Two of the four arrested Tuesday, Joseph C. Blackburn Sr. of Madison, Va., and Wayne S. Morris of Fairfax, remained jailed last night, each under $500,000 bonds.

According to the indictment, the defendants' assets, which may be confiscated under the charges, include McConnell's interest in his law office building and a 43-acre property in Loudoun County belonging to defendants Wayne and James Morris. Also subject to forfeiture were said to be eight automobiles, antiques worth an estimated $868,000 and more than $350,0000 in certificates of deposit and stocks.

The smuggling operation began in 1975, the indictment says, when two of the defendants, Barry Wayne (Fat Man) Toombs and Julian Thomas (Doc) Pernell, allegedly met with an unindicted coconspirator and purchased a $40,000, 41-foot boat named "Banana Quit." The boat was used to transport 5,000 pounds of marijuana into Marathon Key, Fla., from Colombia, the indictment alleges.

Once in the United States, the marijuana was transported to the Tysons Corner area, a pattern allegedly repeated many times in nine years, using several different boats and points of entry along the East Coast.

Harvey, Toombs, Julian Pernell and his brothers, Sidney L. Pernell Jr. and Carl D. Pernell, also are charged with obstruction of justice relating to attempted bribery of grand jury witnesses. In July 1981, the indictment alleges, Harvey offered $200,000 in cash to a grand jury witness.