A police investigation spawned by the rapid growth of largely unregulated bingo games in Northern Virginia has found a consistent pattern of illegal cash payments to workers at contests run by the Annandale Boys Club, according to Fairfax County Prosecutor Robert F. Horan Jr.

Horan said the county police probe is now focusing on other aspects of the Annandale club's games, including its rental arrangement for the Baileys Crossroads bingo hall it uses.

The club often attracts more than 300 people to its five-night-a-week games where bettors wager an average of about $15 apiece. That is a potential gross of about $4,500 a night before about $2,000 in prizes is paid.

The state law that four years ago established bingo and raffles as the only legalized forms of gambling in Virginia states that only "bona fide members" of an organization are permitted to organize, manage or conduct bingo games. In addition, the law dictates that no part of the bingo receipts may "inure directly or indirectly to the benefit of any private shareholder, member, agent or employee" of an organization.

Violations of the bingo provisions are punishable by a fine of up to $1,000 and loss of a bingo operating license for as long as three years.

"You can only use your own people and you can't pay your own people," Horan said. Police investigators declined to say how many of the workers the Annandale club allegedly paid or how much they received.

Everett G. Germain, president of the boys club since 1959, could not be reached for comment. He is reportedly in California on club business. He has not returned numerous telephone calls during the last several weeks.

Club secretary-treasurer Marion Reading, who runs the club's bingo operations, refused to comment on the alleged payments to workers at the games. "The police have gone into this," she said. "You are doing nothing but trying to dig up a lot of dirt."

A financial report filed by the club Dec. 28 in Fairfax Circuit Court lists the payment of $2,125 as "donations paid for help" during the last five months of 1975. The report is not clear whether that money was paid to workers at the games.

The financial report filed by Reading for the Aug. 1-Dec. 31, 1975, period showed receipts of $138,129. Of that, the report said $13,362 was disbursed to the club bus account; $2,635 paid to the club scholarship fund: $19,624 was listed as "cash in bingo bank"; $8,000 to repay a loan from Landlord Investments Inc.; and $57,870 in "rent" to Landlord Investments, an average of about $11,500 a month.

Rent includes "utilities, cleaning, janitorial supplies, repairs & maintenance . . . purchase of equipment," according to the report.

The club's expenditures also included the purchase of bingo supplies, the payment of prizes, insurance and office expenses.

Checks from the boys club to Landlord Investments were paid weekly and varied from $1,695 to $4,845, accoding to the financial report. No two payments were the same and the size of the payments varied in relation to the gross receipts from the bingo game, the report shows, but averaged about 40 per cent of the gross from the bingo games and other club fund-raising activities at the games.

Landlord Investments Inc. is a corporation formed by Robert Gerber and Edward L. Hinkle Jr. The firm leases the bingo hall from the Row Corp, for $2,000 a month before renting it to the Annandale Club.

Gerber said the $57,870 first-year payment included remodeling, installation of air conditioning, purchase of equipment, and complete maintenance.

Gerber, a contractor, said that Germain had approached him concerning the proposed bingo operation. Gerber said his children are members of the Annandale club but that he is not a member. He said that the club paid his corporation $7,250 a month in 1976 and that the corporation was making "a reasonable profit."

Gerber said that he had a similar lease-rent agreement with the five-night-a-week Odd Fellows bingo game in the Shirley Duke Shopping Center in Alexandria, another of the large bingo games in Northern Virginia.

Gerber said he leases that hall for $1,500 a month and receives $3,500 from the Odd Fellows. He said that he has lost money on that arrangement so far.

According to a document filed in Prince William County in support of the Annandale club's recent unsuccessful bingo application there, Hinkle contaccted the owners of a building in the Manassas area and "agreed to help with the building." Gordon R. Hipsley, the club member who signed the Prince William application, said that Hinkle was to be the "landlord" there.

A source in Prince William County said that the bingo hall there would have been leased for $3,000 a month. The Annandale Boys Clubs withdrew its application after local organizations with bingo games protested to county officials and the application became a major local issue.

Club officials Germain and Reading said at the time that their plans were to play bingo only one or two nights a week in Prince William, not five nights as at Baileys Crossroads.

In a related development, State Sen. Charles J. Colgan (D-Prince William) said that he will introduce legislation at the state General Assembly session opening next week to strengthen the state bingo law.

Colgan, who opposed such legislation last year, said the attempt by the Annandale Boys Club to open a bingo game near Manassas had convinced him the law was too weak.