A retired Prince George's County Police officer, John R. Cicala, testified today that the staging of robberies by a so-called police "death squad" in 1967 was "legally and morally wrong" and that he was fired for refusing to participate in them.

Two of the holdup incidents, in which the police killed two men, were "planned from A to Z," including recruitment of the robbery participants, Cicala told a federal jury hearing a $9 million civil rights lawsuit against the police and other county officials. Police have denied the allegations.

Cicala said he complained to the county's chief prosecutor, Arthur A. Marshall Jr., about the incidents shortly after he was fired. Marshall, he said, assured him the prosecutor already had warned Cicala's supervisor that "this type operation had best cease, or some police officers are going to be prosecuted."

Marshall -- a defendant in the current trial -- denies he was aware of any such "death squad" operations.

James L. Shea, an assistant state attorney general representing Marshall, told the jury earlier that neither Marshall nor former assistant prosecutor Benjamin Wolman -- another defendant -- knew of the alleged scheme or approved it. Both Marshall and Wolman are expected to testify.

Survivors of the two men killed, as well as two other men arrested as suspects in the incidents, have sued Marshall, Wolman and three present and former police officers for $9 million. They contend, among other things, that the "death squad" operation violated their 14th Amendment right to due process.

The three policemen, all alleged "death squad" detectives in 1967, are Lt. Col. Joseph D. Vasco Jr., now second-highest ranking official in the county police department, Capt. James Fitzpatrick, now commander of the major crimes division, and retired Lt. Blair Montgomery.

Cicala, who said he was a junior member of the "death squad," testified that Montgomery and Vasco orchestrated the robbery of a High's store in Adelphi on June 8, 1967. He said they instructed police informant Gregory Gibson to recruit two "patsies" to help Gibson pull the holdup, provided Gibson with a getaway car, selected the store to be robbed and set the date and time for the holdup.

On the designated night, Cicala said, Gibson showed up with two participants, William Hunter Matthews and Marvin Rozier, both 18. Several officers, including Cicala, Vasco and Montgomery, had staked out the store.

When the robbery attempt was made, Matthews, who had been armed with a pistol, was shot and killed inside the store and Rozier arrested outside near the getaway car, Cicala said. Vasco then ordered Gibson to "get lost," Cicala said.

As Matthews lay on the floor inside the store, mortally wounded by two shotgun blasts, Cicala testified, another officer, Richard A. Shaner, bent over the dying man and said, "Good-bye, your boy has just done you in" -- apparently referring to Gibson, the informant.

Almost six months later, Cicala said he refused to pose as a clerk in a second planned robbery of a 7-Eleven store in Chillum and was fired. In the alleged holdup on Nov. 26, 1967, the police shot and killed suspect William Clyde Harris, 25, and arrested a second suspect, David E. Wedler, 19.

Cicala said he refused to pose as a clerk "out of fear" and also because "I felt it the staged robbery was legally and morally wrong."

Cicala appealed his dismissal from the police force to the county personnel merit board and was reinstated in 1968. He retired in 1977.

He testified that after complaining to Marshall about the shootings, Marshall "agreed to appear on my behalf" before the merit board.

The "death squad" trial, in its fourth week before U.S. District Court Judge Herbert F. Murray here, is scheduled to last several more weeks, with Vasco and other defendants expected to challenge Cicala's account.