The government of China's Hong Kong Special Administrative Region (HKSAR) on Saturday said an initial investigation by Fosun Industrial and Germany's BioNTech into its COVID-19 vaccine found no indication of  any "obvious systemic factors" during the processes from filling and packaging after the vaccine was suspended in the city and Macao this week.

Authorities on Wednesday halted the use of a COVID-19 vaccine developed by BioNTech as a precautionary measure citing defective packaging.

In a statement published late on Saturday, the city's government said the investigation results did not rule out that the relevant situation was "caused by environmental conditions during the long-haul transport process," adding that it is not related to cold-chain and logistical management according to consolidated figures from the investigation.

Both Fosun and BioNTech considered the vaccines to have no safety risks and people who have received them "do not need to worry," the government said.

The remaining part of the investigation will focus on "ascertaining the integrity of the intrinsic properties of the relevant batches of vaccine, and that the batches are safe for use."

The government said it was following up with Fosun and BioNTech to complete the investigation within a week to allow for a resumption of supplying the vaccines to the public.

The HKSAR on Saturday announced no new local confirmed COVID-19 cases for the first time in more than four months.

The city started vaccinating residents with doses from Sinovac in February and began offering the one developed by BioNTech in March.

(With input from Reuters)