Pakistan's military said on Tuesday that a suicide bomb attack that killed five Chinese engineers was planned in neighbouring Afghanistan, and that the bomber was also an Afghan national.
The suicide bomber rammed a vehicle into a convoy of Chinese engineers working on a dam project in northwest Pakistan in March, killing six people.
"The entire attack was planned in Afghanistan, the car used in it was also prepared in Afghanistan, and the suicide bomber was also an Afghan national," Pakistan military spokesman Major-General Ahmed Sharif told a news conference in Islamabad.
Afghanistan's Taliban-run administration did not immediately respond to a request for comment.
Kabul has previously said rising violence in Pakistan is a domestic issue for Islamabad and denied allowing the use of its territory by operatives.
The Taliban are also seeking economic ties with China, the first country to formally appoint an ambassador to Kabul under the Taliban, and wish to join China-Pakistan Economic Corridor (CPEC), which is Beijing's $65 billion investment in development and infrastructure.
China has stressed to the Taliban the importance of security in the region.
Ahmed Sharif said four main suspects of the plot to target the Chinese engineers have been arrested.
He added that security for 29,000 Chinese nationals in Pakistan, of which 2,500 were working on CPEC projects and 5,500 on other development projects, was the top priority for security institutions.
Relations between Pakistan and Afghanistan have soured in recent months. Islamabad says Kabul is not doing enough to tackle operative groups targeting Pakistan.
Islamabad has gone as far as to say some elements in the Taliban are facilitating the Islamist operatives of Tehreek-e-Taliban Pakistan (TTP) - which is not affiliated with the Taliban, but has long pledged loyalty to the Afghanistan-based movement.
Last year, Pakistan expelled nearly 370,000 undocumented Afghan nationals, saying the majority of suicide attacks against its security forces were carried out by Afghans, a charge Kabul denied.
"TTP militants are using Afghanistan's territory to destabilise the security situation in Pakistan," Ahmed Sharif said, adding that TTP militants were also procuring advanced weaponry from Afghanistan to carry out the attacks.
He warned that the Pakistan military will go to "any extent" to tackle operatives and their facilitators, adding it had previously targeted their hideouts inside Afghanistan.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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