At least 40 people were killed in a suicide bomb attack in Afghanistan's capital city Thursday, CNN and Reuters reported.

Another 30 people were injured during the attack in Kabul, Afghan Interior Ministry spokesman Nasrat Rahimi told CNN.

The attack happened around 10:30 a.m. local time and targeted a cultural center. The first blast was followed by two more explosions, but those did not cause any injuries, Rahimi said.

The Taliban denied responsibility for the attack in a statement to the media released by the group’s spokesman, Zabiullah Mojahid.

The bombing also damaged an office of the Afghan Voice news agency, Reuters reported.

The attack occurred during a morning panel discussion on the 38th anniversary of the Soviet invasion of Sunni-majority Afghanistan at the Tabian Social and Cultural Center, with many of those attending students, witnesses told Reuters.

Sayed Abbas Hussaini, a journalist at the agency, said there appeared to have been more than one explosion during the attack, following an initial blast at the entrance to the compound housing the two offices. He said one reporter at the agency had been killed and two were wounded.

President Ashraf Ghani’s spokesman issued a statement calling the attack an “unpardonable” crime against humanity and pledged to destroy terrorist groups.

“This gruesome attack underscores the dangers faced by Afghan civilians,” rights group Amnesty International said in a statement from its South Asia director, Biraj Patnaik. “In one of the deadliest years on record, journalists and other civilians continue to be ruthlessly targeted by armed groups.”