Four children, aged 7 to 10, and an adult were injured in an explosion in the northwestern Pakistani city of Peshawar early on Tuesday, hospital and rescue officials said.
Bilal Ahmad Faizi, the spokesman for emergency rescue services, said an improvised explosive device (IED) went off on a busy road in Peshawar at 9:10 a.m. (0410 GMT). He said five people, including four children, were injured.
Mohammad Asim, a spokesman for the Lady Reading Hospital in Peshawar, said two of the children were in a critical condition.
There was no immediate claim of responsibility for the attack.
Peshawar, which straddles the edge of Pakistan's tribal districts bordering Taliban-ruled Afghanistan, is frequently targeted by Islamist militant groups including Islamic State and the Pakistani Taliban.
In 2014, six Taliban militants attacked an army-run academy and killed 153 people, most of whom were students. (Reporting by Mushtaq Ali in Peshawar, writing by Ariba Shahid in Karachi; Editing by Neil Fullick)