SPRINGFIELD, Mass. (AP) _ A new grand jury investigating allegations of sexual assaults on students at Westfield State College adjourned without returning any indictments, a prosecutor said Monday.

A grand jury in June indicted former college President Francis J. Pilecki, 52, on charges of sexually assaulting two male students in 1984. Pilecki's attorneys have entered innocent pleas on his behalf.

Hampden County District Attorney Matthew J. Ryan Jr. did not say what aspects of the investigation the latest grand jury considered, but said college administrators, a security official and professors who conducted their own investigation testified.

Ryan's announcement came a day before the 160-member faculty union was scheduled to consider seeking resignations of three trustees who approved a $10,000 payment in January to a student who said he had been sexually assaulted by Pilecki. The three said they did not know about the sexual allegations at the time and cited ''teaching deficiencies'' as the reason for the payment.

Pilecki, who headed the college for six years, resigned in March, saying he had been offered a consulting job at the University of Massachusetts. He has been hospitalized for treatment of depression since his indictment. A pretrial hearing on his case was scheduled for Friday.

Ryan said the grand jury completed its work last week, but said, ''An investigation of this nature is never closed.''

The professors, who began their own investigation when the trustees said teaching quality was the reason for the payment, turned over to the district attorney a list of 22 people they said might have information about the sexual assault allegations.

Ryan said investigators from his office had questioned many of those on the list, but none was asked to appear before the grand jury.