A federal jury in Alexandria yesterday convicted five defendants of conspiracy and cocaine distribution charges in what prosecutors called one of the biggest drug cases ever in the Washington metropolitian area.

The defendants, accused members of a major East Coast drug ring that allegedly sold $500,000 worth of cocaine a month in the Washington area, sobbed and clasped their heads as U.S. District Court Judge Oren R. Lewis said, "Your bonds are revoked. They are in your custody, Mr Marshal."

Lewis decided to revoke bond after being told yesterday by an undercover detective that defendant Michael F. Tillery, described by prosecutors as a leader of the ring, was still engaged in selling cocaine in Alexandria.

Det. Michael E Hubbard also told Lewis that another defendant, Wayne McNair Hargrove, described in court as the ring's boss, face similar drug charges in Detroit and that defendant Marian Teresa Starr had told him she was a prostitute whose chief customer was a Northern Virginia businessman.

Despite defense attorneys' pleas, Lewis said that at age 77 he had "old fashioned ideas" about the need for people to work and that none of the defendants had a job. None had testified to having employment during the year-long course of the police investigation that led to their indictment, Lewis noted.

Lewis set sentencing for Aug. 10 for the five, who also include William Barry Robinson, described during the four-day trial as a lieutenant in the ring, and Paulette Ashton, convicted of helping relay the ring's telephone messages at a posh Arlington condominium.

Each of the defendants faces a maximum of 15 years in prison and a $25,000 fine on the conspiracy convictions. Hargrove, Tillery, Robinson, and Starr also were convicted of illegal distribution of cocaine, and illegal use of a telephone among the charges. Lewis said earlier he would impose concurrent sentences.

One count of interstate travel in aid of racketeering against Ashton was dropped by the government moments before the verdicts were read. The jury of nine men and three women deliberated for nearly six hours yesterday before telling Lewis shortly after 5 p.m. that they were struck on the travel charge. Prosecutors then dropped it.

That defendants and all but one defense attorney declined comment after the verdicts were read. Attorney Christopher Hopkins, who represented Robinson, said he was "disappointed."

Before being led away, Hargrove clasped the head of Ashton, with whom he lived at the Representative condominum building in Arlington during the period of the investigation. Hargrove and Ashton both wept, and Hargrove stumbled as he was led away.

Key prosecution testimony during the trial was provided by Hubbard, a District of Columbia detective who worked with federal drug agents and succeeded in infiltrating the ring.

Hubbard testified he bought a total of nearly $50,000 worth of cocaine from the defendants, whom he met through Starr.

When Hubbard was unable to penetrate the group any furher, a court-approved wiretap was placed on telephones used by Hargrove, Ashton and Tillery, who also lived at the Representative, according to court testimony.

Eleven people were originally indicted. Charges against two were dropped, three pleaded guilty, and one man, known only as "Carolos," is still at large.