At least four people including three Chinese nationals were killed and two injured on Tuesday after a suicide blast targeted a van carrying staff from the Confucius Institute at Karachi University, Aaj News reported.
Television footage first showed a white van in flames and windows of nearby buildings shattered.
Karachi police confirmed four people had died, including the minibus driver and three staff from the Confucius Institute, the cultural and educational programme that China operates at universities around the world.
The banned Baloch Liberation Army claimed responsibility for the attack.
CCTV footage broadcast by local channels then showed a woman standing near the gate of the institute, inside the Karachi University grounds, as the minibus pulls up. When it gets to within a metre she turns her back on it and detonates a bomb strapped to her body.
Speaking to the media, DIG East Muqaddas Haider had initially said three Chinese nationals were among those killed in the blast. They were identified as Confucius Institute Director Huang Guiping, Ding Mupeng, Chen Sai. Driver Khalid was also among those killed. He said initial information showed the van was headed to the institute after leaving the hostel, adding that the explosion took place at the van's right-hand side at the institute's entrance. He said CCTV footage was being analysed and the nature of the blast would only be confirmed after the bomb disposal squad submits its report. The injured – identified as Wang Yuqing and guard Hamid – were shifted to a nearby hospital.
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Prime Minister Shehbaz Sharif also expressed grief over the blast.
"I am deeply grieved on the loss of precious lives including of our Chinese friends in the heinous attack in Karachi today," he tweeted.
"I strongly condemn this cowardly act of terrorism. The perpetrators will surely be brought to justice."
Separately, Sindh Chief Minister Murad Ali Shah took notice of the incident and directed the Counter-Terrorism Department and SSP East to reach the site. CM Shah also directed to immediately shift the injured to Dow University Hospital.
Interior Minister Rana Sanaullah Khan also strongly condemned the van blast at Karachi university.
"There are nefarious motives behind it. The chief secretary and IG Sindh have been asked to submit a report on the blast. We will work alongside provincial governments to ensure the safety of foreigners," he tweeted.
The Confucius Institute hosts programmes for educational and cultural promotion and are funded and arranged by the Chinese International Education Foundation.
Recently, attacks on Chinese nationals have increased in Pakistan, where Beijing is involved in huge infrastructure projects as part of its Belt and Road Initiative (BRI).
Last year, an explosion resulted in the deaths of 13 passengers, among them nine Chinese nationals and two Pakistani soldiers, near the Dasu hydropower plant in the Upper Kohistan district of Khyber Pakhtunkhwa (KPK).
Many in Pakistan believe the attacks are attempts to sabotage the China-Pakistan Economic Corridor (CPEC), which is part of the BRI.
Asad Umar, former planning minister, said the Karachi attack is yet another attempt to derail CPEC and sabotage economic development of Pakistan.
"The whole nation should be united in its resolve to defeat the aims of these anti-Pakistan hostile forces," he tweeted.