Police fired tear gas yesterday into a group of 200 angry farmers blocking traffic on the International Bridge in protest of the importation of agricultural products from Mexico to the United States.

The protesters were routed from the center of the four-lane bridge where they had forced two Mexicans to abandon a truckload of watermelons that jammed traffic on both sides of the Rio Grande for blocks.

Major Roy Eckhart of the McAllen police department and other police officers implored the farmers to move and allow the traffic to clear. When the farmers lingered on the bridge, the tear gas barrage began.

An estimated 1,000 spectators gathered on both sides of the border until the fumes drifted into the crowds. As the farmers moved toward U.S. soil they were met by state troopers standing shoulder to shoulder who ushered them into a fenced area used for vegetable inspections.

The strikers were at the border to protest the importing of crops grown in Mexico with the aid of pesticides that are banned in the United States, such as DDT.

When the farmers were routed from the bridge, at least a half-dozen were knocked to the ground by policemen wielding nightsticks.

Other Brand, Mayor of McAllen -- which co-owns the bridge -- said he sympathized with the farmers' plight but criticized them for confronting police.