A Hamilton teenager said he was forced to eat hot chillies, was abused and held against his will by 10 men in the basement of a city home.

The 18-year-old, who cannot be named for legal reasons, said he was tortured, tormented and abused by the men, who he guessed were in their 30s and 40s.

The native Fijian Indian said he was sexually assaulted, punched repeatedly in the head and forced to eat two bongo chillies.

SUPPLIED Bongo chillies, a type of habanero, are known for their extreme heat.

It began when he and a friend made a prank-call on his cellphone in late February. His friend told him to ring a number and a man answered.

"They started swearing at us, and going off at me. So that's what we did, too, and we started swearing back."

The teen admits calling the man "a motherf-----" in his native tongue.

MARK TAYLOR/FAIRFAX NZ The 18-year-old boy was force-fed bongo chillis and tormented by 10 men.

The following day, the teen was with another friend when he received a phone call from the prank-call number and he agreed to go over to the man's house to make amends.

"He gave me his address and told me to come over at 7.30pm and to be there on time. So my friend drove me over.

"The guy took me around the back to his garage and took me into this basement kind of thing. And when I went in, there were about 10 big-as Fijian Indian guys just sitting there."

When he admitted to being the prank caller, they forced him to sit on a chair and the one in charge started punching him in the head and face while the rest watched.

His friend was told to stay in a corner and not to move, or they would hurt him, too.

Then one of the older men got two bongo chillies and insisted he eat them or he'd be punched.

Native to Fiji, bongo chillies, a type of habanero, are known for their extreme heat.

"I ate one and started feeling faint. My insides were hurting, sweating, and I couldn't see anything or even talk properly," he said. "Everyone was just laughing and watching."

When he couldn't finish the second one, he was punched in the head.

The man in charge then tugged the teen's pants, saying: "I want to see how big your d--- is."

"He said to me because I said motherf-----, he wanted to see how I was going to do that to his mum.

"I told him, it is just a word, I didn't mean it like that, but he wouldn't stop.

"He pulled my pants down and was, like, grabbing it and that kind of stuff.

"Then the guy said, 'What's your parents' number, so we can call them and tell them what you've done?'

His mum, dad, sister and brother arrived quickly. His mum said she could see the bruises on his head and he was clutching his stomach in pain.

"I knew something was wrong, but they kept saying nothing happened, and my son wasn't saying anything at the time," she said. She rang the police and an ambulance.

The mother said when police arrived, officers spoke to both parties, then told everyone to head home and cancelled the ambulance. The family took him to A&E themselves. The teen didn't divulge the sexual assault until the next day.

With that knowledge, the family went back to the police and the case was re-opened.

Senior media adviser Rachel Purdom confirmed police are investigating, but could not comment further.

"We want justice and we want the people involved – whether they were a part of it or witnessed it – to be held accountable," said the teen's mother.

The bongo chilli

The bongo chilli originates in Fiji and is of the Capsicum chinense variety. It is known to be extremely hot.

The chillies are first a light green and then ripen to a bold, bright red. They grow to 6-7cm long and 2-3cm wide, the size of a golf ball.

The Scoville rating is 3500-8000.