Two people died and 19 were wounded, including police, in two bomb blasts in the eastern Afghan city of Jalalabad on Monday, a provincial official said.
The first explosion went off in front of a mosque and, when police and locals rushed to the scene to help the wounded, a second bomb detonated, spokesman Ahmad Zia Abdulzai said.
"In the blasts, two people were killed and 19 people were wounded," said Abdulzai, adding that most of the casualties were from the second explosion.
The target of the blast is not known but there was a meeting ongoing at the mosque in the city's eastern edge, said Abdulzai.
Another provincial official, speaking anonymously, added that pro-government religious clerics had been meeting at the mosque and they may have been the target.
Jalalabad was the scene last month of a major attack when 35 people died and more than 70 were injured after suicide bombers stormed a bank.
The Taliban and other militants have been waging a bloody insurgency against pro-government forces since being ousted by a US-led invasion in 2001.