At least 25 people were injured in an explosion near the Ganj Mandi police station in Rawalpindi on Sunday, rescue officials said.
Rescue 1122 officials said that 22 victims had been shifted to the District Headquarters Hospital, while three were provided first aid on the spot.
Initial reports suggested that it was a hand grenade attack but City Police Officer (CPO) Rawalpindi Mohammad Ahsan Younas said that it was too soon to ascertain the nature of the blast.
The CPO noted that it was the second attack near a police station in 10 days. On December 4, one man was killed and seven other people were injured in a blast carried out using an improvised explosive device near Pir Wadhai police station.
CPO Younas said today that there were reports of terror plots and added that progress had been made in the investigation of the Pir Wadhai blast.
Meanwhile, rescue officials said that the explosion occurred at a filtration plant situated across the Ganj Mandi police station.
The area has been cordoned off and officials of Counter-Terrorism Department and forensic experts have arrived on the scene.
In March this year, seven people were injured, one of them critically, when an explosive device was detonated in the busy Saddar Bazaar.
A similar incident was reported on June 12, when one person was killed while 12 others injured in an explosion in the same vicinity.