The occupation of Mass. Hall by the Progressive Student Labor Movement (PSLM) is straining the resources of the Harvard University Police Department (HUPD), Chief Francis D. "Bud" Riley said yesterday.

"People need to realize that there are resources being siphoned off of other areas of the University to deal with this situation," he said.

Officers are working double shifts to provide the necessary manpower for the PSLM occupation and simultaneously patrol their normal beats.

"We still need to be dealing with the policing needs of the rest of campus while we have officers here," Riley said.

Riley said he is concerned about the stress the protest is placing on officers, many of whom are sleeping only four hours a night. And fatigue will only become a more explosive issue as the protest wears on.

University administrators are currently working with the police union to ensure proper coverage for the campus--methods that might include mandatory overtime for officers in the coming days.

PSLM's occupation is providing one of the first tests of HUPD's "community-oriented policing," a concept that Riley has stressed since his arrival at HUPD in 1995. Riley has attempted to foster an environment in which officers get to know students personally, creating a more secure and comfortable atmosphere.

As part of the initiative, Riley has encouraged officers to eat meals in dining halls and to communicate with individual students to become familiar with their concerns--and has ensured that this approach has carried over into student protests.