Only death will remove me from here. Everyone who has taken part in this oppression will one by one pay for it.
UPDATE 2:20 p.m. EST:
Russia's foreign ministry officially called the assassination of Ambassador Andrei Karlov a terror attack, CNN reports.
Officials have not said who is believed to be responsible for the attack.
UPDATE 2:07 p.m. EST:
National Security Council spokesman Ned Price condemned the attack in a press release from the White House
"This heinous attack on a member of the diplomatic corps is unacceptable, and we stand united with Russia and Turkey in our determination to confront terrorism in all of its forms," the statement read.
The State Department also condemned the attack, adding, "We stand ready to offer assistance to Russia and Turkey."
Russia's ambassador to Turkey, Andrei Karlov, was shot and killed during an art exhibition in the capital of Ankara.
The gunman was later shot and killed by police. Witnesses said the man fired eight shots after yelling "Allahu akbar," Arabic for "God is great."
U.S. State Department spokesman John Kirby condemned the attack and offered "thoughts and prayers" to Karlov's family.
Ankara Mayor Melih Gokcek told reporters the attack was intended to disrupt Turkey-Russia relations.
GRAPHIC VIDEO | Watch the moment the ambassador was shot as a video camera rolled.
Reuters reports the shooter yelled "Don't forget Aleppo, don't forget Syria!" before shooting Karlov. Turkey and Russia have been key players in the civil war in Syria, with Russia supporting Syrian dictator Bashar al-Assad.
GRAPHIC PHOTOS | Here's a look at the shooter standing over Karlov's body after shooting him.
WATCH | Here's the scene after the shooting.
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