London Bridge attack witnesses describe shooting aftermath
"A police officer came up to me and said 'turn off your engine, get out and run'."
Mustafa Salih was behind the wheel of a bus heading towards London Bridge when he was ordered to join the crowds fleeing a sudden violent attack at one of the city's most well-known locations.
That was the moment he realised the bridge had been targeted for the second time in three years.
Mr Salih joined scores running from the scene where two people had been stabbed to death and the suspected attacker shot dead by police.
Just before 14:00 GMT bars and restaurants on the south side of the bridge had been filling up with tourists and office workers.
In an instant that all changed - and London Bridge was in lockdown yet again.
Mr Salih, 62, was travelling from Borough High Street when he saw a stream of people, including some in tears, running towards him.
"A police officer came up to me and said 'turn off your engine, get out and run'," he said.
"I looked up and I could see a crowd of people coming towards me. One woman was crying. It was all very scary as we did not know what was happening."
Nurse Jackie Bensfield, 32, described how she asked to be let off a bus on the bridge after she heard gunshots.
Ms Bensfield, who was on her way home from work, said she got off the bus and "ran like hell" to escape the shots.
Another witness, Connor Allen, who was in his van on the bridge at the time, said: "Everyone just started running, you heard these pops and that was it.
"We just got out [of] the van and started running."
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Shop worker Juan Rios, 35, realised something was wrong when he "heard people running and screaming" and a noise that sounded "like popcorn".
"Then I heard this distant sound coming from the market direction," he said.
"There was one American couple who were separated from their daughter, they were obviously really scared. Afterwards the police came and told us to evacuate."
The bridge remains cordoned off, while nearby Borough Market has also been blocked off by officers and no-one is being allowed through towards the crime scene.
Businesses have been evacuated of shoppers but there is a constant flow of police officers heading into - and out of - the cordon.
London Bridge station was closed and restaurants and bars which had been filling up earlier - and would normally be a hive of activity on a Friday night - were empty.
Workers are being allowed to leave down Borough High Street, but no-one is being allowed through towards the scene of the incident.
Residents have been told to find elsewhere to stay as the police cordon remains in place around the London Bridge area.
Meanwhile, the November night sky is lit up by blue flashing lights, and a helicopter continues to hover overhead.
Shop worker David Lockwood was among those caught up in the incident.
"Most people were very calm, we have practised this after the last attack here two Junes ago," he said.
"It's a shame we have to practise this kind of stuff, but I'm glad we do when things like this happen."