The security officers managed to secure the six floors of the complex, and on Wednesday morning could be heard engaging the militants in a fierce gunfire fight as they tried to flush out the militants who are holed up on the seventh floor.
Heavy gunfire and explosions could be heard as early as 6 am.
The Somalia-based militants have already claimed responsibility of the terror attack, which has led to the death of 15 people and 31 injured.
Most of the rescued were hiding on the first floor of the building under tables, chairs and in the washrooms before security officers rescued them at 4 am.
Dusit workers who are still trapped in the complex are sending whatsapp messages to their relatives pleading for help.
The Dusit complex located in Nairobi’s Westlands area on 14 Riverside drive houses several offices and an upmarket hotel patronized by the middle and upper class Kenyans.
According to the Inspector General of Police, Joseph Boinnet, the attackers forced their way into the 14 Riverside Drive by shooting at security guards at the gate and forcing them to open the gate.
Boinnet said the first explosion that destroyed vehicles and injured several people at the entrance of the building was caused by a suicide attacker.
“But due to the swift response by our officers the situation has been largely contained”.
CCTV footage seen by APA clearly shows four heavily armed Al Shabaab terrorists storming the Dusit complex in a well-organized attack, and could be seen shooting sporadically at innocent victims.
The attack comes as the country marks the third anniversary of the El Adde terrorist attack that targeted Kenyan soldiers in Somalia.
That attack occurred on January 15, 2016 after Al Shabaab militants overrun a military base in the town of El Adde.