Security personnel work at a blast site in southwest Pakistan's Quetta, on June 23, 2017. Picture: Xinhua
Security personnel work at a blast site in southwest Pakistan's Quetta, on June 23, 2017. Picture: Xinhua
Security officials examine the blast site in southwest Pakistan's Quetta, on June 23, 2017. Picture: Xinhua
Security officials examine the blast site in southwest Pakistan's Quetta, on June 23, 2017. Picture: Xinhua
Security officers transfer their injured colleague to a hospital following a suicide blast in southwest Pakistan's Quetta, on June 23, 2017. Picture: Xinhua
Security officers transfer their injured colleague to a hospital following a suicide blast in southwest Pakistan's Quetta, on June 23, 2017. Picture: Xinhua
Injured people receive medical treatment at a hospital following a suicide blast in southwest Pakistan's Quetta, on June 23, 2017.  Picture: Xinhua
Injured people receive medical treatment at a hospital following a suicide blast in southwest Pakistan's Quetta, on June 23, 2017. Picture: Xinhua
Soldiers arrive at a blast site in southwest Pakistan's Quetta, on June 23, 2017. Picture: Xinhua
Soldiers arrive at a blast site in southwest Pakistan's Quetta, on June 23, 2017. Picture: Xinhua
Security officials stand guard at the blast site in southwest Pakistan's Quetta, on June 23, 2017. Picture: Xinhua
Security officials stand guard at the blast site in southwest Pakistan's Quetta, on June 23, 2017. Picture: Xinhua
Security officials examine the blast site in southwest Pakistan's Quetta, on June 23, 2017. Picture: Xinhua
Security officials examine the blast site in southwest Pakistan's Quetta, on June 23, 2017. Picture: Xinhua

Quetta - A suicide car bomber killed at least 11 people, including four police officers, in an attack near a checkpoint in the volatile southwestern Pakistani city of Quetta on Friday, officials said.

Abdul Razzaq Cheema, director general of police in Baluchistan province, told Reuters it appeared the bomber had detonated a car packed with explosives.

At least 11 bodies were taken to hospital, along with 19 wounded people, said Wasim Baig, a spokesman for the Civil Hospital in Quetta.

Four of those killed were police officers, while nine security officials were among the wounded, said Fareed Sumalan, a doctor at the Civil Hospital.

Jamaat ur Ahrar, a splinter group of the Pakistani Taliban, claimed responsibility for the attack in a message sent to Reuters by spokesman Asad Mansur.

Baluchistan government spokesman Anwar ul Haq Kakar said the blast happened near the office of the inspector general of police when officers stopped the car to search it near a checkpoint.

"It's possible the IG office was the target, or the assailants were trying to enter the (army) cantonment which is close by," he said.

Television footage showed emergency services rushing to the scene, which was covered in debris, while security officials cordoned off the area.

The normally busy intersection - which lies between a girls' school, a girls' college, the police office and the entrance to the army cantonment - was relatively quiet because Friday was a public holiday ahead of the Eid celebrations marking the end of the holy Islamic month of Ramadan.

Quetta is about 100 km (60 miles) east of the border with Afghanistan and is the capital of Baluchistan, which has been plagued by militant violence. The province is the base of a separatist movement as well as home to the Taliban and other militant Islamist groups.

It is also at the centre of Chinese-backed "Belt and Road" development projects worth $57 billion that first focused on Chinese firms building roads and power stations but is now expanding to include setting up industries.

Militants from the Islamic State group abducted and killed two Chinese nationals in Quetta last month.

That attack prompted Pakistan to boost security around Chinese nationals and other foreigners in the province, which is already one of the most militarised regions in the country.