At least 20 people were killed Tuesday in Kabul when a suicide bomber blew himself up near a gate at the Afghan Supreme Court, authorities said.

The Ministry of Public Health said dozens more were wounded in the blast. Security forces Brig. Gen. Homyaoon Aiyni told Pajhwok Afghan News the blast took place at about 4 p.m. as workers were leaving for the day.

"When I heard a bang I rushed toward the Supreme Court's parking lot to find my brother who works there," Dad Khuda told Reuters, adding he found his brother alive. "Unfortunately, several people were killed and wounded."

No group immediately claimed responsibility for the attack.

Last month, more than 30 people died when explosions rocked a bus carrying security personnel near the Afghan parliament. Taliban militants claimed responsibility for that attack.

The Taliban controlled most of Afghanistan before being driven out of power following the terror attacks in the U.S. in September 2001. The group continues to carry out attacks across Afghanistan aimed at destabilizing the U.S.-backed, elected government.

The U.S. military has handed off primary responsibility for security in Afghanistan to the Afghan government, although thousands of U.S. forces remain there in mostly advisory and support roles.