The grandson of an acclaimed Kiwi film-maker has been killed in an attack at a popular North London park over the Easter break.

Finbar Sullivan, 21, was stabbed to death and another person was injured after a fight broke out between several groups of people at Primrose Hill early on Tuesday evening local time.

He was the grandson of Kiwi cinematographer and director Michael Seresin, who worked regularly on British director Alan Parker’s films. Seresin owns the Seresin Wine Estate in Marlborough.

Finbar’s father Christopher Sullivan told the Daily Mail that he rushed to the park when he was informed his son was involved, but the young man was already dead when he arrived at the scene.

The former member of 1980s pop British pop band Blue Rondo a la Turk was unsure why Finbar had been targeted in the stabbing.

“I’m so broken-hearted, I can’t believe it. He was the most beautiful, lovely, outgoing, loving boy. He was just a really lovely person.

“His friend was stabbed in the back and hands trying to protect him. My son always tried to stand up for people, so maybe the attacker was bullying someone.”

Sullivan said his son had been a keen film-maker, working on music videos for British drill and rap musicians under the name Sully Shot It.

He had gone to the famous viewing spot to use a new camera he’d bought for his 21st birthday.

“It’s Primrose Hill, for god’s sake ... it’s like Hyde Park. It’s not somewhere you expect this,” he said.

“This is the worst tragedy I could ever imagine. He’s my only son ... I had him when I was 45. He can never be replaced.”

Footage of the attack has quickly spread on social media and shows the brawl escalating as a man wields a knife in front of onlookers, many of whom had gathered in the popular park to enjoy the United Kingdom’s warmest day of the year so far.

One witness told the Daily Mail that several groups of people in their late teens had been involved in the fight.

“The park was just so busy, I had gone with my mate after work and it was literally the busiest I have ever seen it because of the weather and it being Easter holidays.”

“Then suddenly we heard this commotion from behind us, and a big brawl kicked off - people were throwing punches, people were screaming at others to stop.”

Police are continuing to investigate the incident and have asked anyone with information, including photos and videos, to come forward.

It follows a spate of fatal violence in the major city over the last few days.

A man in his twenties was stabbed to death outside a Peckham nightclub on Monday, and another died in a double attack in Shadwell on Tuesday.