Police said Friday that two American missionaries had been found slain at a farm they rented in southwestern Guyana (search) near the border with Brazil.

Residents of the San Jose district, about 12 miles outside the regional capital of Lethem (search), speculated robbery was the likely motive.

The bodies of Richard Hicks, 42, and his wife, Charlene 58, were found Thursday and they were probably killed Wednesday night, police said. The couple's house had been set on fire and the husband's body was burned beyond recognition, police said. His wife was found a few yards away with marks of violence.

"We are not sure yet what exactly happened, but the house was torched," Deputy Police Chief Henry Greene told The Associated Press.

A spokesman for the U.S. Embassy, Wycliffe McAlister, said the Hicks had lived in Guyana for almost a decade, working for the Dallas-based Wycliffe Bible Translators and the Summer Institute of Linguistics in Florida. He said Richard Hicks was born in South Africa and also had Canadian and U.S. citizenship, while Charlene Hicks was a native of Chicago.

Kenneth Glover, a spokesman for the Guyana Bible College (search), said the Hicks were translating the Bible into the Wapishana language spoken by thousands of Indians in the border region, which is a cattle and peanut-farming region about 230 miles southwest of Georgetown, the capital.

"We are not sure what exactly happened," said Glover, of Warsaw, Ind. "They were linguistic experts just translating the Bible in the interior."

Elaine Foo, who runs a bed and breakfast inn near the Hicks' farm, expressed shock at their deaths.

"They were quiet and unassuming, said hello or good morning to everyone, but when people come to rob you in this part of the world they harm you if you don't have money and the Hicks never walked with much money," Foo said.