Palmerston North's St Patrick's Day festivities were marred by news of the death of a young woman believed to have died following a fall at an inner city bar.

Rumours are flying over the final moments of the woman, whose name has yet to be released, after she died on a night out with friends at Palmerston North bar Shooters.

Police reported she had taken a fall and the bar's manager said she died on the way to hospital - not in the bar, as originally reported.

The coroner is now investigating the death of the 20-year-old woman, whose untimely end has left Shooters bar staff shaken.

Bar manager Ricky Quirk yesterday was unable to say how the young woman had died.

"I've heard about 20 different rumours today," he said.

Bar staff were in shock. "It is shocking considering that she was just there with her friends having a good time and 20 to 30 minutes later, she was gone.

"It's tragic," Mr Quirk said.

He had been in Wellington when he was delivered news of the death.

He spoke to bar staff in the early hours of the morning, and they told him the woman died on the way to Palmerston North Hospital.

Police were called to Shooters on Main St on Sunday morning to assist after the woman was reported to have fallen at the bar. It appeared friends of the young woman thought she had fainted but when emergency medical services arrived it was too late, Sergeant Perry Karatau, of Palmerston North police, said.

"A 20-year-old woman had been out with friends. What they think happened is that she fainted.

"They rang an ambulance thinking that she had passed out but by that stage she had passed away."

Police could not yet say whether alcohol was a factor in her death as results of an autopsy were not yet available. The woman's name was expected to be released later today.

- © Fairfax NZ News