There has so far been no claim of responsibility. (Representational)
A roadside bomb killed seven petroleum company employees commuting to work on a packed bus in northern Afghanistan's biggest city, an official and survivors said Tuesday.
Although the Taliban claim to have improved national security since storming back to power in August last year, there have been scores of bomb blasts and attacks -- many claimed by the local chapter of the Islamic State group.
A police official told AFP that Tuesday's blast happened around 7:00 am (0230 GMT) in Mazar-i-Sharif -- an ancient city famed for its beautiful blue mosque.
"I was reading the Koran on my phone screen and there was a boom," survivor Azim, whose right leg was injured by shrapnel, told AFP.
Mohammad Hanif, who was also hurt in the blast, said there were around 52 people aboard the bus at the time.
Seven people were killed and six others wounded according to Asif Waziri, spokesman for the Balkh province police department.
"The bomb was placed in a cart by the roadside. It was detonated as the bus arrived," he said.
There has so far been no claim of responsibility.
At least 19 people were killed and 24 others wounded earlier this month by a blast at a madrassa in Aybak, southeast of Mazar-i-Sharif.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)