One of those killed was a Chinese-American, Pakistan's Daily Times reported.
But other reports said the victim was Chinese.
The group of tourists -- five Ukrainians, three Chinese, and one Lithuanian -- and their Pakistani tour guide were at a hotel in the Gilgit-Baltistan, a mountainous region of northern Pakistan, The New York Times reported, when the gunmen, who were wearing police uniforms, entered the hotel and began shooting. The incident happened at about 1 a.m. Sunday
The gunmen escaped after the attack.
The Pakistan Taliban claimed responsibility for the attack, which it said was in retaliation for a U.S. drone strikes in Pakistan that killed Taliban deputy leader Wali ur-Rehman on May 29, the BBC reported.
Pakistan's Foreign Affairs office released a statement calling the attack a "a heinous crime" that appeared to be "attempting to disrupt the growing relations of Pakistan with China and other friendly countries."
Prime Minister Nawaz Sharif condemned the killings, saying such acts of cruelty and inhumanity would not be tolerated and every effort would be made to make Pakistan a safe place for tourists, The Express Tribune reported
"The people and government of Pakistan stand by you in this hour of huge distress," he told the victims' families.
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