Three cops and one passerby were injured in a grenade attack on a police camp under Karachi’s Quaidabad bridge early on Friday morning, according to police and rescue service officials.

Counter-Terrorism Department Senior Superintendent of Police (SSP) Irfan Ali Bahadur told Dawn.com that police were treating the attack as an act of terrorism. However, he said so far, no one has claimed responsibility for it.

“An initial probe suggested that the suspects threw a grenade from the bridge, which landed in the police camp,” the SSP said.

Malir SSP Kashif Abbasi said in a statement that two personnel of the Police Qaumi Razakars and a Special Security Unit member were among the injured. “One passerby was also hurt,” Abbasi was quoted as saying. “An investigation has been initiated,” he added.

According to a statement from the Edhi Foundation, the injured were identified as Yusuf Amin, 26, Junaid Pervez, 23, Fayaz Muzamil, 26 and Zohaib Qudoos, 25. They were moved to Jinnah Postgraduate Medical Centre for treatment, where their condition was stated to be out of danger.

At the start of March, three policemen were injured in a grenade attack on Karachi’s Preedy police station.

Deputy Inspector General South Syed Asad Raza had told Dawn.com that unidentified people hurled a grenade at the police station, injuring three police personnel, namely Riaz Ahmed, 36, Amir Zafar Iqbal, 34, and Mohammed Arshad, 52.

The injured policemen were moved to a hospital where their condition was stated to be out of danger. Quoting Bomb Disposal Squad experts, the official had said it was a grenade attack.