QUETTA, Pakistan -- The body of a British Red Cross worker held captive in Pakistan since January was found in an orchard Sunday, his throat slit and a note attached to his body saying he was killed because no ransom was paid, police said.

Khalil Rasjed Dale, 60, was managing a health program in Quetta in southwestern Pakistan when armed men seized him from a street close to his office. His captors are unknown, but the region is home to separatist and Islamist militants who have kidnapped for ransom before.

The director-general of the International Committee of the Red Cross condemned the "barbaric act." "All of us at the ICRC and at the British Red Cross share the grief and outrage of Khalil's family and friends," said Yves Daccord.

Safdar Hussain, a doctor who examined the body, confirmed that the throat had been slit. Quetta police chief Ahsan Mahboob said the note attached to it read: "This is the body of Khalil whom we have slaughtered for not paying a ransom."

British Foreign Secretary William Hague condemned Dale's killing, and said "tireless efforts" had been under way to secure his release after he was kidnapped.

Khalil had worked for the Red Cross for years, carrying out assignments in Somalia, Afghanistan and Iraq, the group said.

Quetta, the capital of Baluchistan province, lies close to the Afghan border and for decades has hosted thousands of refugees from that country. The Red Cross operates clinics in the city that treat people wounded in the war in Afghanistan, including Taliban insurgents.

A Pakistani foreign office statement condemned the crime, promising to bring its perpetrators to justice. Arrests for this type of crime are rare, however.

Also Sunday, U.S. missiles killed three suspected Islamist militants sheltering in an abandoned school in North Waziristan, said intelligence officials, who did not give their names because they were not authorized to speak to reporters.

The strike comes as the United States is trying to rebuild its relationship with Pakistan, which opposes the missile attacks and has demanded they stop. The frequency of the attacks, which critics say kill innocents and energize the insurgency, has dropped dramatically this year.

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