Thirteen suspects have been detained over Monday's bombing attack on Chinese engineers at Gwadar port, southwestern Pakistan, Karachi police told Xinhua on Wednesday.

The police official, who insisted on his anonymity, said those detained are all Pakistani nationals from across the country and they are under interrogation in Gwadar.

The Dawn, top English newspaper of the country, earlier quoted official sources as saying that the initial stage of the investigation revealed that a remote-controlled bomb was used in the attack.

The bomb planted in a parked empty pickup blasted on Monday, causing a passing-by bus damage, leaving three Chinese engineers aboard killed, nine other Chinese engineers and two local employees injured.

(Xinhua News Agency May 5, 2004)