Prince George's County Executive Lawrence Hogan, after a meeting yesterday with Maryland state police investigators, announced that he has decided against taking disciplinary action against Joseph Vasco, the acting county police chief, or other officers allegedly involved in a 1967 police "death squad."

Hogan also said that State's Attorney Arthur A. Marshall has concluded that no prosecution is warranted in connection with the "death squad" charges. Marshall, who was recently given a copy of a state police investigative report on the charges, refused to release the report yesterday and would not comment directly on the matter.

The Washington Post reported charges last February that a group of police detectives, including Vasco, had planned a series of convenience store holdups in 1967 in which two suspects were fatally shot.

According to a former detective on the squad and a former police informant, police planned the holdups with informants, then staked out the convenience stores and shot suspect the informants recruited for the holdups.

Hogan asked for the state police investigation of the charges. Although the state police did not give him a copy of their report, Hogan said yesterday that "the investigation disclosed absolutely no information to substantiate the death squad charges.

"Some of the investigative techniques employed by the police department 12 years ago . . . would not be tolerated in our police department today," a statement issued by Hogan said. "However, the conduct of our officers should be judged against the 1967 standards, not the standards of 1979."

When informed of Hogan's statement, Vasco said he was "very pleased that the investigation is now completed, not only for my family and me, but for the police officers of our department and the citizens of Prince George's County."

Last month, Hogan announced that he had dropped Vasco from consideration for the the post of police chief because of the controversy the death squad allegations had created in the community.

So far, the state police report on the carges has not been made public. Maryland Attorney General Stephen H. Sachs said yesterday that the report would be forwarded to Gov. Harry Hughes, who would make the final decision on its release.

"I dont't think the public will be confident about the investigation uness the facts are made public," Sachs said.