"At that moment I thought that these young people are also children of other people, and I didn't want to hurt them and make their parents end up in sadness," said Lau, father of two children.

He said that doctors have arranged an operation on his foot owing to the injury.

A 23-year-old policeman, who wanted to be identified by his surname, Tsang, who worked together with Lau on July 30, said that the radical protesters cast fire extinguishers, water bottles, eggs, and sprayed fluids at them. Tsang was injured after being hit by a fire extinguisher, he said.

Despite the attacks, violent verbal abuse and personal information being leaked on the internet, Lau said he had not heard one single police officer resigning in the past three months.

"We won't give up on our pursuit of our careers because of a small number of people's misunderstanding.

"I believe there is a joint strong belief in the heart of each Hong Kong police officer now, which is to go hand-in-hand with our comrades to end riots and restore social order," he said.

Representing the Hong Kong police force that performed professionally over the past three months, around 10 police officers from Hong Kong, including Lau, have been invited to the grand military parade in Beijing on Oct 1, the 70th anniversary of the founding of the People's Republic of China.

"I'd never regard this opportunity as an honor for me as an individual. Instead, this is the country's and people's recognition for the Hong Kong police force as a whole," Lau said.