A “certain project of a Chinese firm in Pakistan suffered an attack,” China’s embassy says as Islamabad blamed a gas leak.

Local residents and rescue workers gather at the site of bus accident, in Kohistan district of Pakistan's Khyber Pakhtunkhwa province, Wednesday, July 14, 2021.
Local residents and rescue workers gather at the site of bus accident, in Kohistan district of Pakistan's Khyber Pakhtunkhwa province, Wednesday, July 14, 2021. (AP)

At least nine Chinese workers were among 13 people killed on Wednesday when a suspected blast on a bus sent it careening down a ravine in northwestern Pakistan.

The bus was carrying around 40 Chinese engineers, surveyors and mechanical staff to the Dasu dam site in Khyber Pakhtunkhwa province, which is under construction.

Beijing said nine Chinese workers were among 12 people killed on Wednesday by a bomb attack on a bus in northwestern Pakistan and called for severe punishment but Islamabad blamed the explosion on a "gas leak".

Pakistan's Foreign Ministry in a statement said the bus "plunged into a ravine after a mechanical failure, resulting in leakage of gas that caused a blast".

Islamabad is Beijing's closest regional ally but the security of Chinese workers has long been of concern in Pakistan.

Large numbers of them are based in the country to supervise and build infrastructure projects.

"The blast sparked a fire in the engine plunging the vehicle into a ravine, a local government official told AFP, requesting not be named. He said a further 28 Chinese nationals were injured.

A senior local police official, who also asked not to be named, confirmed the incident and said "it was a heavy blast but its nature is not known yet".

Inspector General Moazzam Jah Ansari, the top police official of Khyber-Paktunkhwa, said that police were investigating. 

"Looks like sabotage," Ansari said as he was departing on a helicopter for the site.

"The bus plunged into a deep ravine after the blast and caused heavy losses. One Chinese engineer and one soldier are missing. The rescue operation is launched and the entire government machinery has been mobilised to rescue the injured by air ambulance," another senior government official told Reuters on condition of anonymity.

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China later asked Pakistan to thoroughly investigate the bus blast on Wednesday, the Foreign Ministry said.

Beijing condemned the blast, expressed condolences and asked Pakistan to protect the safety of Chinese personnel, institutions and projects, Foreign Ministry spokesperson Zhao Lijian told a regular news briefing.

The Chinese embassy in Pakistan had earlier also posted a statement on Wednesday, saying that "a certain project of a Chinese firm in Pakistan suffered an attack, which caused the deaths of Chinese nationals".

It urged Chinese firms to strengthen their security procedures.

Deputy Commissioner of Khyber Pakhtunkhwa province's Kohistan district, Arif Javed, said the incident was a result of an accident that took place following overnight rain.

The Dasu hydroelectric project is part of the China-Pakistan Economic Corridor (CPEC), a $65 billion investment plan under Beijing's Belt and Road Initiative that is aimed at connecting western China to the Gwadar seaport in southern Pakistan.

Chinese engineers along with Pakistani construction workers have been working on the Dasu hydroelectric project and several others for several years in the region where the blast took place.

Security of Chinese workers has long been an issue of concern in Pakistan, where Beijing has poured in tens of billions of dollars in recent years, and large numbers of Chinese nationals are now based in the country to supervise and build infrastructure projects.

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Source: TRTWorld and agencies