The incident had taken place as van, carrying three Chinese teachers, was about to enter the Confucius Institute. CCTV footage showed a burqa-clad woman standing outside the entrance of the Confucius Institute who detonated herself just as the van neared the institute's entrance.
Resultantly, three Chinese teachers, including Confucius Institute director Ding Mupeng, who were travelling in the van, and the vehicle's driver were killed.
Acknowledging that there "are also casualties on the Pakistani side", he went on to say that the "Chinese side expresses strong condemnation and indignation over this major terrorist attack, and extends deep condolences to the victims and sympathies to the injured and bereaved families".
He further said the Chinese foreign ministry and diplomatic missions in Pakistan activated the "emergency response mechanism" immediately after the incident, and that Chinese Assistant Foreign Affairs Minister Wu Jianghao made an urgent phone call to Pakistan's ambassador in China.
"The Chinese embassy in Pakistan and consulate-general in Karachi are working with the Pakistani side to deal with the follow-up matters of the casualties," the foreign ministry spokesperson said.
He also mentioned Prime Minister Shehbaz Sharif's visit to the Chinese embassy in Islamabad on Tuesday evening, saying that the premier had conveyed his condolences and the Pakistan government would conduct an "in-depth probe" into the incident, "give exemplary punishment to the perpetrators and strengthen the security of Chinese personnel, projects and institutions in Pakistan in an all-round way".
The spokesperson quoted PM Shehbaz as saying that the Pakistan government would "never allow any force to undermine the Pakistan-China friendship".
According to the spokesperson's statement, local authorities in Sindh and Karachi have already launched a "full-scale investigation to hunt down the perpetrators".
"The Chinese foreign ministry and Chinese diplomatic missions in Pakistan will continue to urge relevant Pakistani departments to handle properly the follow-up matters of those killed, treat the injured, and resolutely crack down on the terrorist organisation involved," the spokesperson said.
"The blood of the Chinese people should not be shed in vain, and those behind this incident will surely pay the price."
Earlier, Sindh Chief Minister Syed Murad Ali Shah had also paid a visit to the Chinese consulate in Karachi where he briefed Consul General Li Bijian about the blast.
The CM had expressed grief over the death of Chinese nationals, assured that the incident would be fully investigated and those involved in the incident would be brought to justice.
Pakistan Ambassador to China Moinul Haque has also expressed shock over the incident and expressed sorrow over the death of Chinese nationals.