Somalia-based extremist group al-Shabab has claimed responsibility for an attack on an exclusive hotel complex in Kenya's capital Monday that sent people refugees from the scene shortly after explosions and shots erupted and left a number of people dead.  A group of armed attackers stormed the complex in Nairobi's Westlands neighborhood, which includes a large hotel known as DusitD2, banks and offices at. Tuesday and ruled terror as people rushed to safety or sheltered inside the buildings, the Kenyan National Police said in a statement.
Pictures from the scene showed several vehicles on fire and some people were carried from the suspected terrorist attack.
"We regret confirming that a group of armed attackers at around 3 pm today [Tuesday] attacked the Dusit Complex in a suspected terrorist attack. The security and emergency teams immediately responded to the incident and cut off the area. The situation is managed and residents screened and evacuated from the area, "police said in a statement.
The hours after the assault began, the extremist group said its warriors were still inside the complex. It is unclear the number of deaths, but a Kenyan police officer who was among the first at the attack said: "There was no time to count the dead, but it is true that there are people who are dead."
Officer, speaking on condition of anonymity, said that some bodies were in restaurants downstairs and that colleagues saw others in offices upstairs scattered among broken glass and blood.
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Police said they were on stage to "engage the attackers."
"We are aware that armed criminals are stopping at the hotel and the special forces are puzzling them. But we are sorry to inform you that there have been injuries in the attack and we are in the process of confirming the number and types of damage incurred, "the statement continued. "We have been vigilant throughout the holiday season and therefore all public and other hotel rooms remain under close surveillance. Reports from across the country show that everything stays calm and normal."
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Several people who worked in the buildings being attacked told Reuters that some of their colleagues were still stored under desks .
"It's awful what I've seen is terrible. I've seen a man when I ran out, and that's what looks like minced meat everywhere," said Charles Njenga, who ran off the stage.
I've saved myself. My colleagues ran everywhere, "another man said, adding that he was hiding in his office." I didn't see an attacker. Yes, it was a terrorist attack. I think so. "
The US Embassy in Nairobi issued a security alert shortly after the reports of the attack occurred.
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"# Kenya Security Warning: Reports of rifles and explosions near the Dusit II Hotel, in the Westland neighborhood of #Nairobi. Notify friends and family of your safety. Avoid the area and move or stay in known safe areas so far, "the alert declared.
Al-Shabab's terrorist government has been blinding the country for years and killing hundreds of people. Tuesday's event comes on the third anniversary of El Adde's battle when al-Shabab extremists launched an attack on a Kenyan military base in Somalia and killed many people.
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In September 2013, four masked men stormed Westgate Mall in Nairobi, of which 67 people were killed and more than 200 people were injured. Al-Shabab later said it attacked the mall because Kenya had sent troops to Somalia to help the UN-backed government.
On Monday, a judge decided that three men accused in the 2013 mall attack should be trial.
Associated Press contributed to this report.