A family are horrified after witnessing a brazen daylight attack on a motorist in central Auckland.

Alina, her husband, their 15-year-old son and 12-year-old daughter were at Burger Fuel on Customs St on Monday when they saw a group of around six youths attack a man sitting in a car.

The attack occurred just after 4pm, she said.

"We're pretty shaken... you don't see these things happen often in front of you," said Alina.

Alina said her husband had yelled at the attackers and that prompted them to run away.

They never got the chance to speak to the victim or to ask him if he was all right as he drove away immediately, she said.

Not long after, Alina and her family were heading back to their car near Britomart when they saw the group again.

Alina said she reported the incident to police and when she called to follow up police had indicated the group were involved in various incidents and multiple reports were received.

Police confirmed they received a report of an incident on Customs St.

"Police are making inquiries into the incident and have no further comment at this early stage."

They are encouraging anyone with information to contact police on 105, quoting job number P050363783.

Information could also be given anonymously by calling Crime Stoppers on 0800 555 111.

Alina said an increase of violence in Auckland, especially in the CBD, is upsetting.

"Every time we go now, we see a lot of different incidents, not major ones, but something is going on always," she said.

"I remember when I was studying at university 17 years ago, I was walking and feeling pretty safe always, but in the past years that has changed significantly."