A Taliban suicide bomber killed at least three people and wounded 27 on Wednesday when he set off explosives in a truck near a police headquarters in Afghanistan, officials said.
A Taliban spokesman, Zabihullah Mujahid, confirmed in a statement that the militants had used a large truck, packed with explosives in the attack in the eastern province of Laghman.
Assadullah Dawlatzai, a spokesman for the provincial governor, said among the wounded were 20 children studying in a religious school.
"The explosion was huge," Dawlatzai said.
The number of casualties may rise as rescuers searched through the ruins of buildings destroyed by the blast.
"We with the rescue teams are still looking for bodies under the rubble," said Obaidullah, a resident of the area.
The insurgent group did not immediately comment.
Located next to the capital Kabul in the east, Laghman has some pockets of Taliban militant presence.
Over the last two months the tenacious spate of bloody violence in Afghanistan has claimed more than 3,000 lives on all sides. Afghanistan is currently awaiting results of the first round of presidential voting, which took place last month. Polling was marred by several small-scale attacks claimed by the Taliban, who worked to disrupt the democratic process.
Meanwhile at least seven Afghan military personnel were killed when the helicopter they were traveling in crashed in the northern province of Balkh on Tuesday, officials said.
According to the Afghan defense ministry, the MI-17 Afghan air force chopper crashed due to "technical faults."
"All the seven crew members including four pilots were martyred in the incident," the ministry said in a statement.
The helicopter had been on its way to a training mission, traveling from an army base near the provincial capital Mazar-i-Sharif when it crash landed on the outskirts of the city, officials said.
Afghanistan has a small air force equipped with fixed-wing planes and helicopters, including aircraft acquired from the United States, the Czech Republic, India and elsewhere.