St John ambulance officers in Christchurch say they are being attacked more and more and have a simple message - please stop.

It comes as a bad batch of synthetics continues to wreak havoc in Christchurch, with one or two affected people still coming into Christchurch hospital each day.

It's proving extra challenging for St John staff, who are finding themselves busier, and in increasingly violent situations.

Checkpoint's South Island video journalist Logan Church spent a 12-hour Saturday night shift with an ambulance crew to find out exactly what front-line paramedics have to deal with.

Watch his video report here: