(NAIROBI, Kenya) -- More than 20 people were killed at an upscale shopping mall in Nairobi after at least one gunman opened fire Saturday afternoon.
The shooting appears to be a terrorist attack. The mall is one of the newest and most popular malls in Nairobi, and has previously been the target of terrorist threats.
Kenyan President Uhuru Kenyatta said in a statement that 39 innocent people were killed and over 150 were injured in the attack. A U.S. official says that three Americans were reportedly among the injured.
The U.S. Embassy in Nairobi has advised Americans to stay home and avoid public places. The U.S. State Department is looking into reports of Americans injured in the attack.
A self-proclaimed spokesperson for Somali group al-Shabab, which has ties to al-Qaeda, tweeted indicating the group's involvement.
"The Kenyan government, however, turned a deaf ear to our repeated warnings and continued to massacre innocent Muslims in Somalia #Westgate," @HSM_Press tweeted.
Kenyan TV is reporting that four gunmen are dead, though the situation is still described as "fluid."
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