Six persons were arrested on drug charges and 20 for alleged gambling violations in separate raids by police in Maryland and Virginia during the weekend.

Three men and a woman were arrested in College Park Friday night for alleged possession of $68,400 worth of cocaine, hashish and methaqualone.

Prince George's County police said the three quarters of a pound of cocaine was one of the largest amounts of cocaine seized in the history of county drug raids.

The arrests were made at the home of Richard C. Holtz, 23, and Susan Andrea Machan, 21, both of 9314 Cherry Hill Rd. in College Park. They were charged with possession of cocaine, hashish and methaqualone.

Phillip Kalman Lang, 21, of 1225 N. Chambliss St. in Alexandria, was charged with possession of cocaine and methaqualone. Mitchell Levine, 23, of 9200 Edwards Rd. in Adelphi, was charged with possession of cocaine.

The four were in jail in lieu of bond, which was set at $40,000 for Holtz and Nachan, $25,000 for Lang and 50 for Levine.

Virginia State Police arrested 20 people Friday night on charges of gambling and frequenting a bawdy house. They were arrested at a house on Princess Elizabeth Street in Fredericksburg.Lottery and card games were discovered at the house, police said.

Virginia troopers also arrested a Fauquier County man on charges of distribution of marijuana and PCP and Douglas Stanley of Stafford County on charges of distribution of marijuana.