WASHINGTON (CNN) -- The FBI is sending a team to Sudan to assist investigators there in their probe of the shooting death of an American diplomat, the agency confirmed Wednesday.
John Granville poses with his mother, Jane, in this handout photo.
The team is already en route to the African nation.
John Granville, 33, was shot and killed along with his driver early Tuesday as he headed home from a New Year's party in the Sudanese capital, Khartoum, his family said.
The U.S. Foreign Service diplomat from Buffalo, N.Y., was working toward restoring peace in war-torn Sudan.
U.S. officials are working with Sudanese authorities to determine if it was a targeted attack or an isolated incident.
"At this point we're not ruling anything out, but we don't know," U.S. embassy spokesman Walter Braunohler said.
Granville's family said there was no particular reason for him to be targeted, as the nature of his work was not political.
Sudanese Foreign Ministry spokesman Ali As Sadeq said the pre-dawn shooting was the result of a "street argument."
He said the streets of Khartoum were packed with cars leaving New Year celebrations and a dispute broke out between people in two cars, one of which was carrying foreigners. Watch I-Report video of shooting scene »
The argument escalated and one of the Sudanese fired on the car carrying the foreigners, resulting in the casualties, he said. E-mail to a friend
CNN's MaryLynn Ryan contributed to this report.
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