URBANA — Striking University of Illinois graduate students occupied the school president's office ahead of another day of negotiations.

The Graduate Employees Organization represents about 2,700 graduate students who teach undergraduate classes. The major issues include tuition waivers and increases in minimum base pay.

The GEO has been on strike since Feb. 26. Protesters on Tuesday opened sleeping bags in hallway outside the office and hung posters with slogans such as "Fund Education First" and "Fair Wages for Grad Labor."

Spokesman Tom Hardy said the students hadn't disrupted business operations in the office, at least initially. President Tim Killeen was not in Urbana on Tuesday, attending to "prescheduled system business."

The two sides were scheduled to meet again with a federal mediator on Wednesday. They have been negotiating for a year.