A bomb threat yesterday afternoon forced the evacuation of Holyoke Center for about one hour.

A University Health Services secretary notified the Harvard police upon receiving a call from a woman who "said simply 'this is a bomb threat' and then hung up," according to a Harvard police report.

Robert L. Conant, Holyoke Center building manager, said the call was received at 12:05 p.m., the evacuation alarm was set at 12:35 p.m., and the building was reoccupied at 1:50 p.m.

"All I know is the buzzer rang and we left," staff assistant Diane Krikorian said.

Conant said police evacuated "mostly the high rise section" of Holyoke Center, including the UHS clinical offices and Holyoke Center administrative offices.

Sgt. William K. Donaldson, patrol supervisor of the Harvard police, said the decision to evacuate was made by UHS Director Dr. David S. Rosenthal '59 and UHS Assistant Director for Human Resources and Operations Gioia M. Morongell.

Donaldson said members of the Harvard police, Cambridge police, and Cambridge fire department searched the building during the evacuation, but found nothing suspicious.