The NDS in a statement said the intelligence operatives have confiscated explosives from a vehicle from the vicinity of the hotel.
The statement further added that the explosives seized from the vehicle carries sign of Biafos Company which produced the explosives and chemicals used in the hotel attack.
A group of heavily armed insurgents launched a coordinated attack on Intercontinental Hotel in Kabul late on Saturday night, triggering a standoff that lasted for almost 15 hours.
According to the Ministry of Interior officials, the attack was launched by a group of at least five insurgents although reports indicate that six insurgents were involved in the attack.
The ministry in a statement said Monday that eighteen people including fourteen foreigners were killed in the attack and nine others including security personnel were wounded.
However, the latest findings show that more twenty people were killed and several others were wounded in the attack.
The Taliban group claimed responsibility behind the attack and accused the victims as occupiers but the government officials are saying that the victims were all ordinary civilians. -KP