Chinese contractors are reported to have halted construction on three hydro-power projects in Pakistan after the suicide attack that killed five Chinese engineers.

On Tuesday, an explosive-laden vehicle hit the bus carrying Chinese engineers on the Karakoram Highway in the Bisham area.

On Friday, a provincial official told AFP that the Chinese companies have demanded Pakistani authorities constitute new security plans before reopening the sites.

As reported around 1,250 Chinese nationals are working on dam projects in Pakistan.

A senior official from the Khyber Pakhtunkhwa Interior Department on condition of anonymity told AFP that since Wednesday, China Gezhouba Group Company has halted work on the Dasu dam in the province and Power China has stopped work on the Diamer Bhasha dam, which straddles two provinces.

“They have demanded new security plans from the government,” he said, adding, “Around 750 Chinese engineers are engaged in the Dasu Dam project, while 500 are working on the Diamer Bhasha Dam.”

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According to the official the movement of Chinese engineers has been restricted to the compounds where they live, close to the sites.

On the other hand, Chinese investigators arrived in Pakistan on Friday to join a probe into the killing of five Chinese nationals in a suicide attack.

According to Pakistan’s interior ministry, the Chinese investigators’ team arrives seeking to stem assaults threatening Islamabad’s drive to modernise the economy.

Interior Minister Mohsin Naqvi met the Chinese team of investigators at Beijing’s embassy. He also briefed them on the investigation so far, the statement said.

The federal minister also met the Chinese ambassador and updated him on the probe into the Besham incident.

The March 27 incident was the third major attack in little over a week on China’s interests in Pakistan, where Beijing has invested more than $65 billion in infrastructure projects as part of its wider Belt and Road initiative.