A cannabis grower has been busted as a result of increased public vigilance prompted by the hunt for fugitive William Stewart.

But police have criticised some local people for keeping information from them.

Police have been chasing 47-year-old Stewart for weeks, mainly in rural Canterbury.

A Toyota Hilux believed to have been used by Stewart was found yesterday in the Mt Somers area, after he was allegedly seen there by a member of the public.

Selwyn police district sub-area commander Senior Sergeant Stewart Munro said as a result of the rural community being on high alert and reporting activity to police, other offences had been detected.

Police responded after suspicious activity was reported in the Darfield area on Monday and discovered a large cannabis growing operation.

A man was arrested and charged with cultivating cannabis for supply, Mr Munro said.

However, while some residents were being vigilant, others in the Mt Somers/Stavely area knew where Stewart had been camping but didn't inform police.

"Some had apparently known of this for four weeks," Mr Munro said today.

"In that period of time Stewart has committed many burglaries and offences throughout Canterbury and in their local area."

Mr Munro said people needed to realise Stewart was a P user and was known to be violent.

He was also known to be in possession of at least two shotguns.

"Other members of the public and police have been put at undue risk."

Mr Munro said people needed to urgently contact police if they believed they had seen Stewart or any suspicious activity.

It was disappointing that some people had not done so, he said.

"Unfortunately police are receiving many calls from the public that have probably been Stewart but not reported until well after the sighting. This is giving Stewart the advantage."

Stewart's ongoing evasion of police has been frustrating for them and Mr Munro today reiterated what sort of person he was.

He described Stewart as a "career criminal, having committed offences throughout his youth and adult life with a history of violence, dishonesty and drug offences".

"He is using methamphetamine which makes his behaviour unpredictable. He shown throughout his life he has no respect for other people or their property. He could be dangerous to the public if cornered."

Mr Munro said Stewart was a danger to police in particular and was likely to resist arrest if cornered. Meanwhile, his offending would continue.

Stewart has now been at large for 10 weeks. A manhunt was launched on February 10 when he allegedly threatened a police officer with an iron bar.