Arlington County Commonwealth's Attorney William S. Burroughs said yesterday that he has new information that might lead to more defendants in the slaying of Arlington real estate salesman Alan Foreman and his fiancee, Donna Shoemaker, or additional charges against the three men already charged in the case.

Burroughs said, however, that he could not reveal either the source of the information or even what the information was, but said that he believed it to be both true and relevant and that it had been "partially corroborated."

Burroughs made the disclosure in Arlington Circuit Court in support of the trial of Richard Lee Earman, one his unsuccessful motion to postpone of the three now charged, until late September. Earman's trial is scheduled to begin Monday morning, which, Burroughs said, was "too close in time" for him to make use of the new information.

In addition, Burroughs said that the new information "may change the commonwealth's theory of the case" against Earman, and might cause him to not present some of the evidence he said he now as against Earman. Burroughs refused to elaborate, however, on what his theory of the case is or how the information might change it.

John K. Zerling, Earman's attorney, said that if Burroughs "was not prepared to go to trial" he should "not have indicted (Earman) in the first place." He called Burroughs reasons for asking for the postponement "one of the most pitiful excuses I've ever heard."

Arlington Circuit Court Judge Charles Russell denied Burroughs' request, saying the prosecution had had ample opportunity to determine the timing of the case from the beginning.

In other developments yesterday, attorneys for the other two defendants, Joseph P. Martin and Charles Silcox, asked Russell to quash the subpoenas requiring their clients to testify at Earman's trial.

Russell said he would give the attorneys his decision on the subpoenas on Monday, beforeEarman's trial begins.