According to the police, the bomb planted in a car exploded with a big bang in the Kala Bari market area of Peshawar, the provincial capital of the country's northwest Khyber Pakhtunkhwa province.
Security forces, police and rescue teams rushed to the site and shifted the injured to the Lady Reading Hospital of the city. All the wounded persons are reportedly in a stable condition.
Police said the preliminary investigation showed that a big quantity of explosives was planted in the car and it was parked in the market.
Police feared that the miscreants wanted to attack the market during busy hours. However, the bomb exploded accidentally in the morning when the market was closed, police said.
Over 12 shops and several vehicles were also damaged in the explosion. Law enforcement agencies cordoned off the area and started a search operation.
No group has claimed the explosion yet.