The FBI said today agents are on their way to Sudan's capital to assist the State Department in investigating the death of a USAID worker there.

"The FBI will provide investigative assistance to State Department investigators concerning the murder of USAID employee John Michael Granville in Sudan," FBI spokesman Special Agent Richard Kolko told ABC News.

The State Department investigators will include agents of the department's Bureau of Diplomatic Security.

Granville, along with his Sudanese driver, was shot and killed as he was heading home after midnight on New Year's Day.

According to an internal State Department incident report, the attack happened minutes after Granville dropped off a female colleague at her home around 2:15 a.m. local time.

Granville, who attempted to get out of the car when the shooting began, was shot repeatedly.

The attackers fled once residents came out of their homes, apparently disturbed by the sound of gunfire.

Granville was first taken to a local clinic and then to a Khartoum hospital. Although he was talking while being treated, the staff was unable to get any details out of him before he died, according to the report.   

State spokesman Sean McCormack offered his condolences today, saying the shooting started the year off "on a note of sadness."

He said the department still doesn't know the motive for the shooting or who is responsible.

Granville was a well-respected volunteer in Africa.

In 1997, he became an official volunteer for the Peace Corps and served in the village of Bamendjou in Cameroon, where he was bestowed the honorary title of "Notable" by the village chief upon his departure, according to a U.S. government official.

In Sudan, Granville and his driver were "deeply committed to their work and highly respected by their colleagues in Sudan and throughout our organization," a USAID statement said.

USAID is the leading international donor to Sudan, having contributed more than $2 billion since fiscal year 2004.

Krista Kjellman contributed to this report.

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