Police used tear gas and water cannon on Monday against protesters occupying Hong Kong Polytechnic University. The situation remains tense. Police surround the campus. They say they will use force against the protesters if they do not leave. Students barricaded themselves in to stop police from entering several places. They have used gasoline bombs against police vehicles and set fires. The president of the university said he has negotiated a truce with police. Teng Jin-Guang said the agreement would permit hundreds of protesters trapped at the university to leave peacefully. Teng said he received promises from police for a temporary suspension of the use of force if the protesters do not act against police.