Officials say at least 17 people have been killed and more than 40 wounded, including a prominent parliament member, in a suicide bombing in eastern Afghanistan.
A powerful blast occurred during a demonstration against the acting governor of Khost Province in the provincial capital.
Provincial Deputy Governor Abdul Wahed Pathan said a suicide bomber blew himself up in the crowd.
The Interior Ministry said 17 people were killed.
Humayoun Humayoun, the head of the parliamentary defense committee, was among the wounded.
No group has immediately claimed responsibility for the attack.
Meanwhile, in the country's south, a district police chief was killed amid fierce clashes between security forces and Taliban militants.
In the southern province of Helmand, officials say fierce clashes broke out overnight after Taliban militants attacked police checkpoints in Gereshk district.
A local official, who requested anonymity, told RFE/RL that the gunbattle was still under way hours later.
Officials said there were casualties but it was unclear how many.
Helmand provincial police chief Nabi Jan Malakhail said district police chief Hikmatullah Akmal was killed by a roadside bomb.
Malakhail said the explosion occurred early on April 2 as Akmal was heading toward the site of a Taliban attack on a checkpoint.
A major military operation is underway to drive Taliban militants from the Helmand River valley.
The Taliban and other militant groups often target Afghan officials and members of the security forces.
There has been no let-up in attacks following the formal end of the NATO and U.S. combat mission in Afghanistan in December.
About 9,800 U.S. troops remain in the country.
During a visit by Afghan President Ashraf Ghani to Washington last week, the White House announced that it would halt the drawdown of U.S. troops from Afghanistan, maintaining 9,800 troops through the end of 2015 instead of cutting the force in half as previously planned.