Sohail Khalid, district police chief in Charsadda district where Shabqadar is located, confirmed the suicide attack and said three of the dead were policemen.
According to initial reports, a suicide bomber entered the complex and a policeman on duty tried to stop him but he blew himself up,” Khalid said. The policeman Mian Naseemullah did his best to stop the attacker and ended up sacrificing his own life for this.
He told journalists that the attacker was aged between 15 and 16 years old. He said three cops including a woman constable were critically injured and currently under treatment at Lady Reading Hospital.
Shabqadar is near the Mohmand tribal district, one of seven semi-autonomous regions bordering Afghanistan where militants from Al-Qaeda and the Taliban had established bases in the past.
The government launched a military offensive in the tribal areas in 2014 that has reportedly killed thousands of militants and pushed the rest over the border to Afghanistan, resulting in improved security inside Pakistan.
Law enforcement agencies also arrived on the crime scene shortly after the blast and cordoned off the area for investigation.
Sources said the intelligence agencies had warned of terrorist attack in Charsadda and the information had been conveyed to the relevant departments.
Shabqadar is some 30 kilometres (18 miles) west of Charsadda, where extremists attacked a university on January 20 in a rampage that left 21 dead.