"Out of the blue, a voice boomed out over the club's sound system: 'Could all the New Zealanders please leave the premises immediately'."
Initially the New Zealand team thought the announcement was a joke, but then realised the seriousness of the situation once it was repeated.
Scuffles started breaking out once the team left the venue.
Shocked at what was unfolding, Carter and fellow future All Black star Luke McAlister fled the venue and the pending violence.
"We didn't know it yet, but that one random, somewhat selfish decision might have ended up saving lives," he said.
"As soon as we left things exploded. Players started brawling with the bouncers. But what sent the whole scene over the edge was when reinforcements arrived not long after."
That included several fans arriving and "big security types piled out".
"It became a scene of extreme violence, and guys from both sides were getting seriously beaten up. The whole thing had a level of violence way beyond the average pub brawl.
"Then gunshots rang out."
The gunfire saw members of the New Zealand Under-21 team seek the refuge of their team vans.
"Sam had been pistol-whipped, Jason Shoemark had copped a hell of a beating," Carter wrote.
"As the vans tried to leave, the windows were smashed in - guys were jumping fences, just running for their lives."
When Carter and McAlister rejoined their team-mates at their hotel, he wrote they were greeted by the sight of "carnage".
"There were guys with blood everywhere, guys missing teeth, guys with eggs on their heads, broken noses, black eyes," he recalled.
"It was horrifying. Everyone was terrified, scared for their lives."
Of the gun fire, Carter wrote: "I still don't know if guns were being shot at people, or whether security guards were just shooting in the air to put the s**** up them.
"It doesn't really matter - the fact that they had guns and were pistol whipping guys and pointing them at us made the situation by far the most serious and intense I'd encountered at any point in my playing career."
Carter returned to South Africa in 2003 with the Crusaders during that year's Super 12.
He was to endure more off-field horror after being robbed during a night out in Cape Town.
"Out of nowhere two guys came up, grabbed me and pinned me up against a wall," he wrote in My Story.
"One of them demanded my phone, but I was a bit drunk and cocky. 'It's alright', I replied, 'I'm talking on it'.
"'Get your gun out and shoot him', I heard. My blood ran cold. I handed him the phone, put my head down and walked off as quickly as I could, my pulse racing, entirely sobered up."
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