U.S. Customs Service agents seized video game machines valued at $250,000 in searches yesterday at 19 Northern Virginia locations in connection with a federal investigation into imported counterfeit video games, officials said.

The agents executed search warrants on the offices and warehouse of Hunter Vending Corp. at 607 S. Ball St., Arlington, as well as 18 locations where Hunter-supplied video machines were being operated, according to a statement by the U.S. attorney's office in Alexandria.

Hunter Vending is a major dis- tributor of video game machines in Northern Virginia, the office said. Hunter Vending officials could not be reached for comment.

U.S. Attorney Henry E. Hudson said yesterday that 80 machines and 30 video game components were seized in the raids. The establishments from which the machines were taken, which included recreation centers, convenience stores and an Alexandria hotel, are not targets of the investigation, Hudson said.

The searches were part of an investigation into the importation of counterfeit video games in violation of federal copyright and trademark laws, according to Hudson's office. No charges have been filed in connection with the probe, which is continuing, he said.

According to an affidavit by customs agent William H. Gonzalez filed in U.S. Magistrate's Court in Alexandria, the video game industry "has been experiencing the introduction of counterfeit computer boards and video game displays from Korea."

In most cases, the games are imported through Canada "in hopes of a more lenient customs examination," the affidavit said.

The imported games, which often bear counterfeit copyright markings, are cheaper than the games made in the United States, sometimes half the price, Hudson said. The electronic components of the video games are imported in kit form, assembled, then inserted into the video games' wooden frames.

Robert S. Fay, director of enforcement for the Alexandria-based American Amusement Machine Association, said yesterday that the Korean-made counterfeits are a "huge problem" for the video game industry, resulting in a $40 million loss for the industry in 1985.