Secretary for Security Chris Tang said on Saturday that police will step up patrols throughout the city, following a recent series of attacks that sparked safety concerns, but urged the public to do their bit to identify people with problems.

Speaking on a radio programme, Tang said officials will mobilise more frontline staff in busy areas.

He said they would also ensure that security personnel report suspicious cases to the police as early as possible.

Tang dismissed concerns that Hong Kong is no longer a safe city.

"There's no need to worry too much. But we understand people's concerns after such events," he said.

Tang called on the public to do their part and to pay attention to the mental health of those close to them.

"Overall, I think we should pay more attention to our friends and family members to see if there's any problem - and seek help as early as possible," Tang said.

Safety has been in the spotlight after three incidents recently.

On Friday, a police said a man chased a secondary school pupil at a Wong Tai Sin shopping mall with a knife.

That incident came just a day after a woman was stabbed near Choi Hung MTR Station, and just over a week after two women were stabbed to death at a mall in Diamond Hill.