Auckland police have released video footage showing bike thieves in action, following a surge in bicycle thefts from public areas around the central city.

Titled Gone in Six Seconds - the video shows the thieves, often in pairs, swiftly moving in on a locked bike, cutting the cable and cycling off within a few seconds.

Most shockingly, they are often committing the crime as people walk or drive by without noticing.

The first clip shows a father working with two sons to steal a bike, police say. The dad clips the cable and walks away as one boy jumps on the bike and rides off.

Later that day both boys and their father were caught by police attempting to steal another bike outside AUT University, police say. The father was charged with theft and is currently in custody.

Police are urging cyclists to use the heavier D-locks, which cannot be cut easily with bolt cutters.

"Lots of the bikes that get stolen are worth hundreds to thousands of dollars, but when it comes to the lock, we often find owners are using a $20 lock that is easy to snip," says Acting Inspector Graeme Anderson.

"We're doing our very best to catch these offenders and to prevent this from happening in the first place, but it's a constant battle and we need bike owners to help us by making it hard for the criminals," he says.

The footage shows that even if you park your bike in an area where lots of people are around, brazen thieves will not be deterred, he says.

"The other challenge for us is that we're catching up with these people and recovering the stolen bikes, but often we have no idea who the bike even belongs to.

"In many cases people aren't reporting that their bike has been stolen, as a result we have dozens of unclaimed bikes that we can't return to the rightful owners.

"If you record your serial number, or buy a UV marker pen and write your cellphone number on the bike, it means we can prove it's stolen, and get it back to you," he says.

Newshub.