A United Nations investigator called on Chile’s government to stop using an anti-terrorism law against Mapuche Indians who are fighting to recover their ancestral land.

Violence from the Mapuche struggle escalated last year with a string of arson attacks, including one that killed an elderly couple. Their deaths shocked Chileans and raised questions about the inability of President Sebastian Pinera’s government to meet the demands of Chile’s largest indigenous group and his administration’s vow to continue using tough dictatorship-era measures to curb the violence.

Ben Emmerson, the UN special investigator on human rights and counter-terrorism, on Tuesday said the situation is “volatile” in the southern regions of Araucania and Bio Bio, where most of the nearly 1 million Mapuche live.

Speaking after a two-week visit to Chile, he warned “that it could turn into a major regional conflict unless urgent action is taken to deal with the acts of violence.”

He said Chilean prosecutors have enough legislation “at their disposal to investigate and punish crimes” without the need to use the terrorism law that dates from Gen Augusto Pinochet’s 1973-90 dictatorship.

There was no immediate response from Chile’s government.

Mr. Emmerson said Chile’s government should come up with a strategy to solve the dispute, recognize the country’s largest indigenous community under the constitution and speed up the return of their lands. He said that otherwise it could take decades at the current rate things are moving.

A radical faction of the Mapuche have occupied and burned farms and lumber trucks to demand the return of lands. Werner Luchsinger (75) and wife, Vivian Mackay (69) were killed last year when attackers torched their home in the heart of the indigenous land conflict. The only man arrested for the crime is a Mapuche.

Police have been accused of violent abuses, including storming into Mapuche homes during raids and shooting rubber bullets during demonstrations.

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