Cache of firearms found at Christchurch man’s home, and he later dies from a stab wound after police surrounded his car.

New Zealand police launched a “high-priority” investigation on Wednesday to find out whether a man who died after an early morning standoff with officers had links to the mosque attacks that killed 50 people.

Police raided the 54-year-old man’s home on Tuesday night and found a cache of firearms after receiving a tip-off from the public about “suspicious behaviour”, Police Commissioner Mike Bush said in a statement.

“A high priority investigation is under way to determine whether or not the deceased man posed a threat to the community,” said Bush.

They stopped the man in his car just outside the city of Christchurch and began negotiations that lasted for about three hours.

Police eventually approached the vehicle and found the man critically injured with a stab wound that soon claimed his life. They did not explain how he got the wound but a knife was located in the vehicle.

There were no firearms in the car, however, which was also cleared by explosives experts.

Any involvement?

With Christchurch on alert after New Zealand’s gun mass shootings less than two weeks ago, police said they would also look for any links to the mosque attacks.

“At this time there is no evidence to suggest this person had any involvement in the attacks of March 15, however, this forms an important part of the investigation,” said a statement.

Christchurch will host a national memorial for the attack victims on Friday and police have urged the public to remain vigilant.

Wednesday’s police investigation comes as New Zealand’s intelligence minister said he was allowing spy agencies to carry out “intrusive” activities following the gun rampage.

The government this week ordered a judicial inquiry into whether the South Pacific nation’s intelligence services could have prevented the attack amid criticism the white supremacist gunman went unnoticed as they were too focussed on the Muslim community.

“I have given authority to the agencies to do intrusive activities under warrant,” said Andrew Little, the minister responsible for intelligence services.

Little told Radio New Zealand that spies typically monitor 30-40 people, but that number had now increased – although he was unwilling to reveal by how much.