An Australian tourist lost his life on night out with mates while on a California holiday.

Victorian native Matthew Bate was a scientist and his family said they have lost a warm and kind soul.

The 33-year-old was knocked out when an argument outside his San Francisco hotel turned physical.

It was on a small set of concrete stairs in the middle of the night when Mr Bate's overseas trip with mates ended in horrific circumstances.

View photos Australian man Matthew Bate died after a fight in San Francisco. Source: 7 News More

"I saw lots of paramedics and policemen and someone lying on the footpath," said Australian tourist Rod McLennan.

That someone was Mr Bate, a metals scientist who grew up in Ocean Grove before moving to Darwin just a few months ago.

His family has told 7 News he was smart, lived life and was dearly loved.

View photos Mr Bate died after a fight outside his hotel. Source: 7 News More

Now, two people have been detained by the San Francisco Police Department over his death.

"No weapons have been mentioned. No guns, no knives at this time," said SFPD's Giselle Talkoff.

"But again, all of it's going to be looked into, what exactly transpired."





View photos Australian tourist Rod McLennan was woken in the commotion. Source: 7 News More

It is believed Mr Bate had been with his mates at a nearby bar, but a fight broke out when they got back to their hotel.

Australian tourists Rod and Marilyn McLennan were staying at the same hotel and were woken by the commotion.

"It looked like there's been a fight and someone's hit their head on the ground," Mr McLennan said, adding police then stormed every room looking for those responsible.

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