Taliban bombers have attacked an Afghan police convoy outside the capital Kabul, killing at least 30 people and wounding 50 others, officials say.
Two bombs hit a convoy of buses carrying graduates from a ceremony on the city's western outskirts.
The bombing was claimed by the Taliban and follows an attack on a bus just over a week ago that killed 14 people.
The victims in the 20 June attack included Nepali security guards working for the Canadian embassy.
In the latest violence, interior ministry spokesman Sediq Sediqi said there had been two blasts targeting the cadets.
Officials are still trying to confirm the precise number of dead but witness and sources describe a scene of carnage.
Kabul's police chief is at the scene of the attack, some 20km (12.5 miles) west of the capital.
The cadets were returning to Kabul from a training centre in Wardak province and were about to go on leave.
According to the governor in Paghman district, which is en route, a suicide bomber struck first, followed by a second car bomb explosion detonated between two buses in the convoy.