Several young Brits were among 22 tourists robbed at gunpoint on a bus in Peru .
Adella Clarke, 28, said six men in balaclavas stormed the bus in the Amazon jungle on Sunday.
The attackers said "just kill them" when one person resisted in the chilling horror.
Ms Clarke was in her first week of a month-long backpacking trip with three friends, Somerset Live reports.
There were around seven other Brits in different parties on the bus, travelling from Puerto Maldonado to an eco lodge in the jungle with the travel company G Adventures.
The masked thugs pounced around 30 minutes into the journey along a remote rural track.
"Suddenly the bus came to a halt. I was sitting by a window, there was a lot of shouting in Spanish.
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"The bus doors opened and man in a balaclava came on board.
"There were six of them stood in the middle of the dirt road pointing guns at the bus," Ms Clarke, a care assistant, said.
The tourist, of Midsomer Norton, Somerset, said the driver was urged to drive away but the tour guide objected in fear that the attackers would shoot if he did.
She said: "They were each taking it in turns to come on the bus and grab bags.
"Our tour guide said 'just give them what they want. Don't resist'.
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"I had a gun in my face while my friend was having his wallet taken out of his pocket.
"My other friend had a gun pointed to his head while the bag under him got taken.
"A lady resisted and the tour guide later on said they were shouting 'Just kill them, just kill them'.
"The ordeal lasted about seven minutes.
"Everyone was shook up. They eventually ran off into the jungle.
"They were firing shots at the locals who tried to help."
The bus was then driven on to a village where they phoned police.
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But Ms Clarke, who was traveling with pals from Ipswich, Suffolk, said: "We couldn't phone the police straight away.
"We were just waiting in another remote village thinking 'are they going to come back', like sitting ducks. That was the worst bit."
She said the group were "escorted back to the main town by police who gave little interest" and have since been transferred to the capital Lima, but "seriously shaken".
She praised the response from G Adventures.
"The assistance has been very good.
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"They've put us up in a nice hotel, they've been great about it ... provided us with stuff to do and checked in on us."
Despite the ordeal she plans to continue on her trip.
She leaves for Bolivia today (Wednesday, April 17) and then will go to Argentina.
"We're not getting buses anymore. This is too much of a shock so we're going to fly everywhere from now on.
"We did it the right way - through a tour company - to avoid dangers like this but it still happened."
