Prime Minister Imran Khan has called Chinese Prime Minister Li Keqiang and expressed his condolences over the death of Chinses citizens in the Dasu bus blast and assured him of all-out efforts to investigate the incident, reported 24NewsHD TV channel on Friday.

Prime Minister Khan assured his Chinese counterpart Li Keqiang that the provision of security to the Chinese citizens was the first preference of the Pakistan government. He said that enemy forces would not be allowed to damage the brotherly relations between China and Pakistan. 

He told Mr Keqiang that Pakistan was providing the best medical facilities to the Chinese who got injured in the incident. 

China's Foreign Ministry condemned the incident as a "bomb attack." "China has asked the Pakistani side to thoroughly get to the bottom of the truth as soon as possible, arrest the perpetrators, severely punish them and earnestly protect the safety of Chinese personnel, institutions and projects in Pakistan," spokesman Zhao Lijian said at a press briefing in Beijing on Wednesday. 

China yesterday also postponed an annual meeting of the Joint Cooperation Committee of the China-Pakistan Economic Corridor (CPEC) which was supposed to be held today (Friday). No new date has been announced for it so far. 

Prime Minister Khan while addressing a conference in Tashkent on Friday said that the CPEC project would bring peace and security to the region. 

Pakistan on Thursday conceded that a blast on a bus carrying Chinese workers, which killed nine of them, could have been caused by explosives, after having initially termed the incident an accident. 

Information Minister Fawad Chaudhry tweeted that initial investigations of Wednesday's incident have "confirmed traces of explosives" and that terrorism has not been ruled out. 

A total of 13 people, including four Pakistanis, were killed in the incident that involved a bus carrying workers of the Dasu hydropower project in Khyber Pakhtunkhwa province.

Pakistan Foreign Ministry had initially claimed that the blast was caused by "mechanical failure resulting in leakage of gas," Kyodo News reported. Foreign Minister Shah Mehmood Qureshi had told his Chinese counterpart Wang Yi that a preliminary investigation had shown that it was an accident and nothing to suggest a terrorist attack was found. 

Fawad Chaudhry said Prime Minister Khan is personally supervising the case and the investigations are being closely coordinated with China. "We are committed to fight menace of terrorism together," he said. AFP reported that construction of the Dasu dam on the Indus River began in 2017 and was scheduled to be built within five years, according to the Pakistan Water and Power Development Authority.

Reporter Awais Kiyani

With inputs from Agencies