Associated Press
Undated photo shows John Granville, center. He was killed on Tuesday by gunmen as he was being driven home in Khartoum.

KHARTOUM, Sudan — U.S. diplomat John Granville knew his work toward restoring peace in Sudan put him in harm's way, but he told his family he wouldn't want to do anything else.

Granville was shot and mortally wounded early Tuesday in Khartoum by gunmen in a passing car who cut him off as he was being driven home in Sudan's capital. Sudanese officials insisted it was not a terrorist attack, but the U.S. embassy said it was too soon to determine the motive. Granville's driver, Abdel Rahman Abbas, was instantly killed in the shooting.

The Sudanese government often drums up anti-Western sentiment in the media. But attacks on foreigners are rare in Khartoum, where an American diplomat was last killed in 1973.

Granville, 33, who was from Buffalo, was an official for the U.S. Agency for International Development, known as USAID. He was working to implement a 2005 peace agreement between Sudan's north and south that ended more than two decades of civil war, USAID said. Granville initially survived the attack with five gunshot wounds to the hand, shoulder and stomach. He died after surgery, said Walter Braunohler, the public affairs officer at the U.S. Embassy in Khartoum.

Africa had been "very special to John" since his time as a Peace Corps volunteer in Cameroon, his family said in a statement Tuesday.

"He told his mom several times ... that it's dangerous, what he's doing, but he wouldn't want to be doing anything else," said U.S. Rep. Brian Higgins, who spoke with Granville's mother, Jane Granville, after her son's death.

Officials were working to return Granville's body to the United States, possibly by today or Thursday, the Buffalo-area congressman said.

Granville, who last called his mother on New Year's Eve, graduated from Fordham University and got a master's degree in international development from Clark University, his family said. While in the Peace Corps, he helped a Cameroon village build its first school.

"John's life was a celebration of love, hope and peace," the family's statement said. "He will be missed by many people throughout the world whose lives were touched and made better because of his care."

Granville was being driven home about 4 a.m. when another vehicle intercepted his car, the Sudanese Interior Ministry said. Gunmen in the car opened fire on Granville's vehicle and fled the scene, the ministry said in a statement.

Higgins said the pair had been in a car with diplomatic plates, and investigators are trying to determine a motive.

"They don't know if it was random or if it was targeted for USAID or targeted for John," Higgins said.

Higgins, a member of a House subcommittee for international relations in emerging threats, has been to Sudan twice and praised the work of agencies like USAID "for doing the work that government over there won't do and can't do."

Granville's work included bringing radios to residents of south Sudan to maximize USAID's broadcasting initiatives in the region, according to the organization's Web site, which posted pictures of Granville surrounded by some of those who received radios.

Sudan's Foreign Ministry said the incident was "isolated and has no political or ideological connotations" and pledged to bring the culprits to justice, according to state news agency SUNA.

The Sudan Media Center, which has close links to the government, cited an unidentified government official as saying the attack was criminally motivated and that there was "no grain of suspicion of an organized terrorist action."

However Braunohler, the embassy spokesman, said it was "too early to tell" whether the attack was terror-related. Because of an ongoing investigation, he said he could not comment on any of the details provided by the Sudanese.

The shooting came a day after a joint U.N.-African peacekeeping force took over control in the western Sudanese region of Darfur, where more than 200,000 have died in a conflict that began in 2003. Al-Qaida has called for a "jihad" or holy war, in Sudan against the peacekeepers.

But al-Qaida has shown little overt presence in the country in recent years since the Sudanese government threw out Osama bin Laden in the late 1990s.

Al-Qaida was blamed in the 2002 assassination of an American USAID officer, Laurence Foley, who was gunned down outside his home in Amman, Jordan.

Humanitarian aid workers have come under increasing attack in Darfur by the region's multiple armed groups, but such attacks have not been known to take place in Khartoum.