One male and six female Chinese, as well as two Pakistanis, were abducted from the acupuncture clinic where they worked in the early hours of Saturday by students from a radical mosque, before being released later in the day.

Students from the Red Mosque and Jamia Hafsa female seminary raided the clinic, which they alleged was being used as a brothel.

China's Public Security Minister Zhou Yongkang on Tuesday called on Pakistan to take further measures to ensure the security of Chinese workers and property, according to the Xinhua report.

"We hope Pakistan will look into the terrorist attacks aiming at Chinese people and organisations as soon as possible and severely punish the criminals," Zhou told visiting Pakistani Interior Minister Aftab Ahmed Khan Sherpao.

In response, Sherpao said Pakistan would take more rigorous action to safeguard the security of Chinese people and organisations in Pakistan, Xinhua added.

China has refused to comment on allegations the kidnapped workers were involved in prostitution, saying only they were running a business in Pakistan that had all the necessary legal licences.