Three men were stabbed at a gym before their alleged attacker fled in a stolen BMW and robbed two service stations at knifepoint.
Police say the alleged attacker fled the fitness centre in Brookvale in Sydney's Northern Beaches on Monday night in a stolen BMW.
The man, described by witnesses as 'agitated and aggressive', then carried out two armed robberies at service stations in Newcastle, NSW Police said in a statement.
Three men were taken to Royal North Shore hospitalised after they were stabbed at a gym on Pittwater Road in Brookvale in Sydney's Northern Beaches
The alleged attacker fled the scene in a stolen BMW and has been connected to two armed robberies in Newcastle later on Monday night (scene at the gym pictured)
The first occurred at Sandgate about 9.45pm when a man threatened a female worker, 38, with a knife and smashed the cash register.
He forced the register open and fled with the cash in the stolen BMW.
About 15 minutes later, at 10pm, a man walked into a second service station on Maitland Road and placed two chocolates on the counter.
As the 24-year-old employee opened the till the man jumped onto the counter and produced a knife while demanding cash.
The employee complied and the man ran from the store and fled the service station with the stolen cash and car, police said.
Officers responding to the armed robbery saw the stolen vehicle leaving the service station and pursued; however it managed to evade police.
The man is described as Caucasian in appearance, about 168cm tall. He has a full beard and is aged in his mid to late twenties. He was described as wearing black shorts and a light coloured t-shirt.
No-one was injured during the robberies.
A manhunt is underway and the alleged attacker has been described as armed and dangerous (scene at the gym pictured)
A crime scene was established at both service stations as police from Newcastle City conduct further inquiries.
The registration plate of the vehicle and description of the man matches that from the triple stabbing at the gym on Pittwater Road.
In that incident, he entered the gym about 8pm and approached four men and a trainer.
The man allegedly punched one of the men before producing a knife and stabbing three of the men, who were all taken to Royal North Shore Hospital.
One of the men was taken straight in for surgery. All three, aged 26, 29 and 31, are now in a stable condition.
The trainer managed to escape injury.
Police are appealing for anyone who may see the vehicle, a black BMW with NSW registration DKK 39Q, or has any information that may assist the investigation, to contact either Newcastle City or Northern Beaches police.
As he is believed to be armed with a knife police are urging members of the public not to approach him but to call triple zero immediately.