By Frank Jack Daniel

GUATEMALA CITY, Mar 15 (Reuters) - At least one person was killed and several injured in Guatemala on Tuesday when police tried to disperse a protest against a controversial free trade agreement. Protesting teachers and farmers say the police fired live rounds as they tried to clear a demonstration from a road 180 miles (290 km) north of Guatemala City close to the border with Mexico in the highland region of Huehuetenango.

"(The protesters) say the dead man was shot at point blank range ... but this will have to be established by appropriate authorities," said Huehuetenango Governor Mauro Guzman.

Staff at a local hospital said four people were receiving emergency care for bullet wounds after the incident and one was in critical condition. More wounded were expected.

The shootings follow a series of clashes in recent days between police and protesters angry at a new free trade agreement approved by the Guatemalan Congress on Thursday.

On Monday, riot police backed by the army used water canons and tear gas to battle thousands of protesters, many armed with gasoline-bombs and rocks.

Central American governments hope the contentious U.S.-Central American Free Trade Agreement, or CAFTA, will lower or eliminate tariffs on their exports.

Critics in Central America say patent rules included in CAFTA will limit poor people's access to lifesaving drugs, and many worry that small farmers will be unable to compete against subsidized U.S. agriculture.

Guatemala, Honduras and El Salvador have approved the pact, considered the most explosive trade issue before the U.S. Congress this year. In the United States, CAFTA has languished in Congress while the Bush administration tries to round up support for the agreement.