Foreign Minister Shah Mahmood Qureshi told his Chinese counterpart that preliminary investigation into the bus tragedy near Dasu hydropower project in the Kohistan district of Khyber Pakhtunkhwa was not a consequence of a terrorist attack, according to a statement on China's foreign ministry website.
The statement, issued on Thursday, said Qureshi met Chinese foreign minister, Wang Yi, on the sidelines of the Shanghai Cooperation Organisation-Council of Foreign Ministers in Dushanbe on Wednesday.
In the meeting, the statement added, Yi stressed the immediate arrest of and severe punishment for perpetrators in case the incident was a terrorist attack.
Qureshi, however, said the initial probe showed that the incident was not a terrorist attack.
"He [Qureshi] said preliminary investigation shows that it's an accident and no background of terrorist attacks has been found," the statement read.
The statement further quoted the Chinese foreign minister as saying that if the incident was "a terrorist attack, the criminals must be immediately arrested and severely punished".
"Lessons should be learned from the incident, and the security measures for China-Pakistan cooperation projects should be further strengthened to ensure the safe and smooth operation of all projects," he stressed.
Qureshi said China was Pakistan's "most important friend and most reliable partner, and China's loss is Pakistan's loss," according to the statement.
"Pakistan will spare no effort to rescue and treat the wounded, thoroughly investigate the truth of the incident, lose no time in sharing the progress of the investigation with China, and do its utmost to ensure the safety of Chinese personnel in Pakistan," the statement quoted him as saying.
On Wednesday, thirteen people, including nine Chinese nationals, two personnel of the Frontier Constabulary (FC) and two locals, were killed and 28 others sustained injuries when a coach carrying them to an under-construction tunnel site of the 4,300-megawatt Dasu hydropower project fell into a ravine in the Upper Kohistan area after an explosion.