A suicide attacker has struck near the Kabul police academy, killing at least 15 and wounding eight others, officials said, in the second major attack in the Afghan capital in 24 hours.

“A suicide bomber on foot blew himself up near the academy,” Deputy Interior Ministry Spokesman Najib Danish said on Friday.

“Casualties are expected.”

The incident, which comes as cadets were returning to the academy after their two-day weekend, marks a serious breach of security at a premier training institute for Afghan security forces.

Kabul Deputy Police Chief Gul Agha Rouhani confirmed the suicide attack.

The bomber was dressed in police uniform and managed to get close to a group of officers before detonating his explosives, another security official told AFP news agency, requesting anonymity.

Heavily-armed security officials cordoned off the area and ambulances with wailing sirens were seen rushing to the scene.

The academy in west Kabul is a premier training institution for police forces in Afghanistan, with between 2,000 and 3,000 cadets graduating every year.

The bombing comes less than 24 hours after a truck bomb tore through central Kabul, killing 15 civilians and wounding 240 others in the first major attack in the Afghan capital since the announcement of Taliban leader Mullah Omar’s death.

No group immediately claimed responsibility for either of the attacks, which come as the Taliban steps up their summer offensive despite a bitter power transition within the armed group.

The carnage comes a day after Taliban fighters killed nine people in multiple attacks on police targets, including a truck bombing in the volatile eastern province of Logar.