Police have uncovered no new leads in connection with Sunday's firebombing at Tufts University's Fletcher School of Law and Diplomacy.

An FBI spokesman said last night that federal agents-who have been working on the case since Monday-are trying to determine whether a federal violation is involved in the case. Carool Farmer, night manager of the bureau's Boston office, said that in terstate activities such as the transportation of explosives across state lines would bring the offense into federal jurisdiction.

Medford police captain Robert Glynn, who is heading the investigation, said last night that police had not yet determined the authenticity of a note from a group calling itself, "the Arson squad" which claimed responsibility for the bombing.

Police are now questioning several of those who were in the vicinity of the fire around the time of the blast. The state fire marshal and the state chemist are continuing their investigation in cooperation with the Medford Fire Department.

Glynn confirmed that a person who was seen running into a Fletcher dormitory shortly after the firebombing was a Tufts student.

The student reportedly feared that the fire in Mugar Hall would spread to the nearby dorm and pulled a fire alarm. "He checked out all right," Glynn said.

Glynn added the police are still investigating the report of a student who said he saw two person running away from the building immediately after the bombing.