Somali-based terror group Al-Shabaab now claims its followers are behind the attack at Riverside Drive, Westlands this afternoon.
They have claimed responsibility through Radio Arm, which is linked to them. They said their members are inside the upmarket building still fighting.
The attackers struck Dusit Hotel alongside bank and other offices within the Riverside this afternoon. Initial reports indicated there was a blast followed by heavy gunshots.
The attack comes hours after Milimani Law Court acquitted one of the four suspects charged over Westgate Terrorist attack in 2013.
At the moment there is heavy security there, including bomb experts. Government has not issued statement but the top cops including DCI George Kinoti is on the ground leading the counter-assault.