Police said the officer, surnamed Wu, who was on duty at the time of the accident, and tested negative for alcohol, the CNA said .

But a test on the victim showed a high level of alcohol, the CNA report said.

The family of the man said they were concerned that police would not be impartial handling the investigation, and they would invite third-party independent people to take part in the probe.

Police maintained their impartiality, saying they would screen the CCTV footage in the area to determine the cause of the accident.