(CNN) -- Brian Adkins, a newly assigned American diplomat in Ethiopia, was found dead last weekend at his home in the Ethiopian capital, Addis Ababa, an embassy spokesman and a senior State Department official told CNN.
U.S. Embassy press officer Michael McClellan identified Adkins and said he was from Columbus, Ohio. He was 25 at the time of his death.
"He was found dead over the weekend and a criminal investigation is under way," McClellan told CNN on Thursday. "The Ethiopian federal police are investigating it."
Adkins, who would have turned 26 on Monday, received his undergraduate and graduate degrees from George Washington University, according to the school's newspaper, the GW Hatchet, which reported his death.
According to the newspaper, Adkins joined the State Department after receiving his master's degree in 2007.
A State Department official, who declined to be named because of the ongoing investigation, said it was the diplomat's first tour of duty as a foreign service officer. There were no apparent threats against him, and investigators were trying to determine whether he was the victim of a random crime.
Adkins' father, Dan Adkins, told CNN affiliate WBNS that his family worried about him, but Adkins assured them he would be safe at a guarded compound.
His sister, Tiffany Cooper, said the family was struggling.
"It is hurting us. There is no closure. We have no idea how our brother died," Cooper said.
The GW Hatchet reported that Adkins moved to Ethiopia as part of a Thomas R. Pickering Foreign Affairs Fellowship, after studying the local language and culture for nearly a year.
A GWU student and friend of Adkins described him as "selfless, hardworking, confident, funny, charming, articulate, a scholar and a gentleman," according to the newspaper.
"The world has lost someone who had so much to offer. I miss him tremendously," senior Michael Geremia told the newspaper. "When I received word of his death on Monday, which would have been his 26th birthday, a piece of me died in Ethiopia."
As a student, Adkins was active in the Knights of Columbus and the Newman Center, which are organizations run by the Catholic church, the paper reported.
-- CNN's Elise Labott and Ben Brumfield contributed to this report.
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