A suicide bomber Thursday killed at least 13 people and wounded around 40 others, including a prominent Afghan lawmaker.

A suicide bomber Thursday killed at least 13 people and wounded around 40 others, including a prominent Afghan lawmaker, in an explosion near an anti-corruption protest outside the complex housing the governor of eastern Khost province, officials said.

"Thirteen dead bodies and 39 wounded people were brought to hospital," Aminullah Khan, a doctor at the government hospital in Khost city, the capital of the province which borders Pakistan, told AFP.

A senior local police official requesting anonymity said 20 people were killed and 40 others were wounded.

Humayoun Humayoun, a well-known MP from Khost province, was wounded in the explosion, he added.

Protesters accusing the provincial governor of Khost of rampant corruption and land grabbing have staged demonstrations outside his residence for nearly a week.

No group has so far claimed responsibility for the attack, but suicide blasts have been a weapon of choice for the Taliban in their 13-year battle against the US-backed government and foreign forces.

The bombs often target Afghan security forces, but they have also taken a heavy toll on civilians.

The number of civilians killed and wounded in Afghanistan jumped 22 percent in 2014, a recent UN report said, as NATO troops withdrew from combat.

The United Nations Assistance Mission in Afghanistan attributed the rise to an intensification in ground fighting, resulting in a total of 10,548 civilian casualties last year.

The Taliban, waging a deadly insurgency since they were ousted from power in late 2001, warned that the announcement would damage any prospects of peace talks as they vowed to continue fighting.