At least three people died including a senior police officer when a roadside bomb exploded in Quetta, the capital of Pakistan's restive Balochistan province.

At least 18 people were injured in the incident, including four police officers.
At least 18 people were injured in the incident, including four police officers. (AFP)

At least three people have been killed and 18 others injured in a bomb blast in Pakistan's troubled southwestern province of Balochistan, which borders Afghanistan and Iran.

The roadside explosion occurred on Wednesday as a police van traveled through the provincial capital, Quetta.

"At least three people are dead including a senior police officer," Fida Hussain Shah, a senior police official, told AFP, adding that the attack was believed to have targeted police.

"It was an improvised explosive device and apparently two to three kilograms of explosive was used," he added.

He said 18 people were injured in the incident, including four police.

Waseem Baig, a spokesperson for Quetta's Civil Hospital, also confirmed the death toll while putting the number of injured at 25.

Balochistan is Pakistan's largest and poorest province despite being rich in natural resources.

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Baluch insurgency

Pakistan is fighting several low-level insurgencies in the province, waged by separatists and sectarian groups.

No group has yet claimed responsibility for the attack; however, Baluch separatists in recent months have increased attacks on security forces.

Last month, at least nine soldiers were killed after insurgents attacked two army check posts in the province.

Tensions have been stoked further by a flood of Chinese investment under Beijing's Belt and Road Initiative, which locals say has not reached them.

China is investing in the area under a $54 billion project known as the China-Pakistan Economic Corridor, upgrading infrastructure, power, and transport links between its far-western Xinjiang region and Pakistan's Gwadar port.

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Source: TRTWorld and agencies