Updated

An Afghan army helicopter crashed Wednesday in bad weather in the western Farah province, killing all 25 people on board, including the deputy corps commander of the western zone, a provincial spokesman said.

Mohammad Naser Mehri, spokesman for the Farah governor, said the helicopter crashed around 9:10 a.m., shortly after taking off from the mountainous Anar Dara district heading toward the nearby Herat province.

On board were the corps commander, Gen. Naimudullah Khalil, and two members of the Farah provincial council, its chairman, Farid Bakhtawar, and Jamila Amini, one of only two women on the nine-member council.

Taliban spokesman Qari Yusuf Ahmadi claimed the insurgents had downed the helicopter but failed to provide evidence. Defense Ministry spokesman Ghafor Ahmad Jawed rejected the Taliban claim of responsibility as "totally wrong."

Wednesday's was the second army helicopter crash in as many months in Farah. In September, five crew members died when their helicopter crashed. Investigators blamed the crash on a technical failure, without elaborating.

Elsewhere in Afghanistan, a suicide bomber struck outside the country's largest prison on the edge of the capital, Kabul, killing seven people, including prison workers and security personnel, said Interior Ministry spokesman Najib Danish. The attacker targeted a bus carrying prison workers, he said. The sprawling Pul-e-Charkhi prison houses hundreds of inmates, including scores of Taliban insurgents.

Abadullah Karimi, a prison official, said the attack occurred near the prison gate where visitors were waiting to pass a rigorous security check before entering. The SITE Intelligence Group, which monitors militant websites, said the Islamic State affiliate in Afghanistan claimed responsibility for the suicide attack.