(Warning: graphic violence)
WATCH: Circa obtained this exclusive security camera footage from the Supreme Court in Kabul, Afghanistan. It shows the moments before a suicide bomber detonated his vest, killing dozens and wounding more than 40 people.
The footage was taken from security camera is facing away from the courthouse and shows people walking to the parking lot seconds before the bomb blast.
An Afghan intelligence official told Circa, "Nobody can enter the court building area without a proper search, so questions are now being raised as to how this young guy entered the area with an explosive vest."
The Afghan intelligence official, who spoke on condition of anonymity, said they are investigating the incident.
Various reports out of Afghanistan over the past several days have suggested that ISIS was behind the attack. SITE intelligence group, which monitors terror activity on the Internet, says a video released by ISIS names Abu Bakr Altajiki of Tajikistan as the bomber.
However, western officials tell Circa that the investigation is ongoing and that in a "region complicated by various terrorist networks, situations are not always clear."
ISIS has established pockets of control in Afghanistan's eastern Nangarhar province, but terrorists have infiltrated areas of the nation's capital, a western official told Circa.
If validated by Afghanistan and western officials, it will be the second attack in the capital by ISIS.
Last November, ISIS targeted the Shi'ite Baqir ul-Uloom mosque in the Darulaman area of the city, killing dozens and wounding more than 80 people.
The suicide bomber detonated his suicide vest “between the entrance of the building and the parking lot” around 3:45 p.m. just as employees were exiting and entering the building, according to Sediq Sediqqi, a spokesman for Afghanistan’s Interior Ministry.
Reports out of Afghanistan suggested the attacker was targeting a bus that court employees use to get to and from work.
Italian army Lt. Gen. Rosario Castellano, deputy commander of the NATO mission in Afghanistan, said in a statement "anyone who seeks to destabilize the pillars of a functioning government are enemies of Afghanistan."
A number of Supreme Court judges and lawyers were inside the building when the bomb went off and people in the area that witnessed the explosion said they could feel the ground shaking beneath their feet. The supreme court is located on the main road inside the city and its employees have been targeted by the Taliban in the past for convicting members of the organization.
“I was leaving the court building when suddenly a heavy explosion took place and I saw many people were crying but I lost consciousness and really it was a doomsday for me,” said Rahmatullah, who was wounded in the explosion, told Circa on phone.
Afghan president Ashraf Ghani, condemned the attack, saying in a statement, "this act the enemies of the Afghan people once again showed their enmity towards the people.”
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This story was updated Feb. 9, 2017 as information became available.
Sajid Khan contributed to this report from Pakistan.