Separatist militant attacks on police stations, railway lines and highways in Pakistan's restive province of Balochistan, coupled with retaliatory operations by security forces, have killed more than 70 people, officials say.
The most widespread assault by ethnic insurgents in years forms part of a decades-long effort to win secession of the resource-rich southwestern province, home to major China-led projects such as a strategic port and a gold and copper mine.
"These attacks are a well thought out plan to create anarchy in Pakistan," Interior Minister Mohsin Naqvi said in a statement, adding that security forces had killed 12 militants in operations after the attacks, but without giving details.
The largest of the attacks targeted vehicles from buses to goods trucks on a major highway, killing at least 23 people, officials said, with 35 vehicles set ablaze.
Rail traffic with Quetta was suspended following blasts on a rail bridge linking the provincial capital to the rest of Pakistan, as well as on a rail link to neighbouring Iran, railways official Muhammad Kashif said.
Police said they had found six as yet unidentified bodies near the site of the attack on the railway bridge.
Officials said militants also targeted police and security stations in Balochistan, which is Pakistan's largest province, killing at least 10 people in one attack.
Militant group the Baloch Liberation Army (BLA) took responsibility in a statement to journalists that claimed many more attacks, including one on a major paramilitary base, though Pakistani authorities have yet to confirm these.
The BLA is the biggest of several ethnic insurgent groups that have battled the central government for decades, saying it unfairly exploits Balochistan's gas and mineral resources. It seeks the expulsion of China and independence for the province.
Prime Minister Shehbaz Sharif said the attacks were aimed at stopping development projects that form part of the China-Pakistan Economic Corridor (CPEC).
"The terrorists want to stop CPEC and development projects," Sharif said in a televised address to cabinet on Tuesday.
Sharif added the purpose was to drive a wedge between Islamabad and Beijing.
CPEC, said to have development commitments worth $US65 billion, is part of Chinese President Xi Jinping's Belt and Road initiative.
In Beijing, China condemned the attacks and vowed to keep up firm support for Pakistan in counter-terrorism efforts.
"China is ready to further strengthen counter-terrorism security co-operation with the Pakistani side in order to jointly maintain regional peace and security," Lin Jian, a foreign ministry spokesperson, told a regular news briefing.
Militants have targeted workers from the eastern province of Punjab whom they see as exploiting their resources.
In the past, they have also attacked Chinese interests and citizens in the province, where China runs the strategic southern deepwater port of Gawadar, as well as a gold and copper mine in its west.
Balochistan, which borders both Iran and Afghanistan, is Pakistan's largest province by size, but the least populated and it remains largely underdeveloped, with high levels of poverty.
