Police are questioning a man about six armed robberies across the northern suburbs last night.
At one of the incidents the offender was armed with a syringe and at another intimated he was armed with a gun.
The offences are believed to be linked, the first occurred 8.49pm at the Craigie Tavern bottleshop on Eddystone Avenue in Craigie.
At 12.51am the perpetrator robbed a Gull Service Station in Burswood.
He then moved on to a BP Service Station at 3.50am on Main Street, Osborne Park.
The man then targeted a Caltex Starshop on Wanneroo Road in Northlands at 4am and a United Petroleum Service station on Walter Padbury Boulevard in Padbury at 9.33am.
He was last seen at 9.52am at a Coles Express at the corner of Marmion Avenue and Marina Boulevard in Ocean Reef
Police said a 35-year-old man was helping Regional Investigations Unit officers with the investigation into the robberies.
Anyone with information regarding these incidents is asked to Call Crime Stoppers on 1800 333 000.