(CNN) -- American teacher Ronnie Smith has been shot and killed in Benghazi, according to the Facebook page of the international school in Libya where he worked.
The U.S. State Department confirmed the killing and identified the educator as Ronald Thomas Smith II.
"The untimely death of Ronnie Smith has been felt by the whole school community," the International School Benghazi posted on its Facebook page. "He was a much loved teacher who supported students in their learning and always had time to help when asked. Ronnie was a professional who gave his time freely and without question. We do not understand why this has happened and it is extremely difficult for his students and his colleagues to accept."
The page was full of comments from Smith's students and those who knew him, praising him as a dedicated educator.
"Mr. Smith was an exceptional teacher, my sons broke into tears," Bint Altayar wrote. "They love him so much, they always mention his sense of humor and kindness. We are very sorry for his death. This is a tragedy, he and everyone in Libya (Libyan and non Libyan) don't deserve this. I think every foreign teacher should leave until Libya is safe."
Smith exemplified "respect, optimism, cooperation, team work," posted Noor Hewaidi. "He believed in his students, and that's the greatest gift any teacher can grant a child. And we're thankful for that. Let's continue to live by his principles, let's finish the job he started."
Deputy State Department spokeswoman Marie Harf said that officials are reaching out to family members and providing "appropriate consular assistance."
She told media that the State Department offers condolences.
White House spokesman Jay Carney said that President Barack Obama has been briefed on the matter. Carney said that no one has taken responsibility for the death.
"We look to the Libyan government to thoroughly investigate this killing," Carney said.
U.S. Ambassador to Libya Deborah Jones tweeted: "Libya's enemies will not succeed in driving away her friends" and "My heart goes out to the family of the American school teacher murdered today in Benghazi."
Harf said there would be no further comment for now and referred questions to Libyan authorities.
The Interior Ministry has opened an investigation into the incident, according to a statement reported by Libya's state news agency LANA.
It said four unidentified assailants in a black Jeep opened fire on Smith, killing him instantaneously.
"This cowardly act in no way reflects the morals and traditions of the Libyan society," LANA reported the ministry said.
It also reported a statement from the Foreign Ministry, which vowed to bring those responsible to justice.
Reports of the slaying, including a story filed by Reuters on Thursday, said that gunmen killed an American chemistry teacher working at an international school in Benghazi.
Reuters cited medical and security sources.
"He was doing his morning exercise when gunmen just shot him. I don't know why. He was so sweet with everyone," Adel al Mansouri, the director at the school in Benghazi, told Reuters.
Benghazi, Libya's second-largest city, is where militants attacked a U.S. diplomatic mission in September 2012, killing four Americans, including Ambassador Chris Stevens.
More than two years after the fall of Moammar Gadhafi's regime, the Libyan government has been struggling to control the country, which is awash in weapons and armed groups. The security situation has deteriorated over the past year, especially in Benghazi, which was the cradle of the 2011 revolution.
The United States blames one of the armed groups, Islamist militant group Ansar al-Sharia, for the deadly attack on the U.S. mission in Benghazi.
CNN's Jomana Karadsheh and Jim Acosta contributed to this report.