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JALALABAD, Afghanistan, April 11 (Xinhua) -- Some 12 cadets were killed and 38 people were wounded after a suicide bomber targeted an army bus in Afghanistan's eastern province of Nangarhar on Monday, officials said.

Photo taken on April 11, 2016 shows a destroyed bus at the site of a suicide attack in Nangarhar province, eastern Afghanistan. At least 12 people were killed and more than 20 others wounded after a suicide bomber targeted a police academy vehicle in Afghanistan's eastern province of Nangarhar on Monday, an official said. (Xinhua/Rahman Safi)

"The bomber rammed a tricycle bomb to a mini-bus carrying military students at around 4:30 p.m. local time. The incident occurred in Sorkhroad Square in outskirts of provincial capital Jalalabad city," a security official told Xinhua anonymously.

The stricken bus veered off the road and several vehicles around the site were damaged by the force of the explosion. The bomber also died on the spot, he noted.

"Those killed included 12 persons aboard the bus and several civilians from other running vehicles also sustained injuries," Attaullah Khoagyani, spokesman of provincial government, told Xinhua.

The bus was travelling from Jalalabad to Afghan capital of Kabul.

The injured were shifted to hospitals in the city, 120 km east of Kabul, he said.

No group has claimed the responsibility for the attack so far. Fighters of Taliban militant group and Islamic State (IS) outfit have presence in remote districts of the province.

The Afghan security forces have beefed up security operations against militants recently as spring and summer known as fighting season is drawing near in the country.

However, the militants responded by targeting the so-called soft targets by attacking government workers and conducting suicide attacks, targeted killings and roadside bombings.