Auckland police have patrolled 94 petrol stations overnight, after a spate of robberies in the region.
Detective Inspector Glenn Baldwin said there had been five incidents across the city since Sunday - two aggravated robberies in Western Springs and Green Bay, and burglaries in Papatoetoe, Glen Eden and Remuera.
In response, police were stepping up patrols, he said, particularly at businesses and petrol stations that operated 24 hours a day.
"From Warkworth in the north, to Tuakau and Mercer in the south, our frontline staff have prioritised visiting forecourts and providing reassurance to staff."
Police had made progress on other investigations, Baldwin said. Five people, aged between 13 and 19, have been arrested in relation to 10 aggravated robberies at South Auckland petrol stations in December and January.
Another teenager was arrested yesterday for the aggravated robbery of a Mt Roskill TAB on February 29.
"Late yesterday, a search warrant was executed at a Mt Roskill address where a 16-year-old male was arrested and charged with aggravated robbery."
The police were anticipating further arrests, after linking that crime to an aggravated robbery three days later at a Western Springs petrol station.
"Like our community, police are appalled at some of the violent behaviour that has been inflicted on people just doing their job," Baldwin said.
"We will continue to work to hold offenders to account that are inflicting harm on businesses and their employees."