A hostage spoke of his terror after a gun was held to his head by a man during a three-hour bank siege.
Dan Beedell was one of around 15 people taken hostage in Barclays Bank in Church Road, Ashford, west London.
A man in his 30s was arrested in connection with the incident and was today in police custody, Surrey Police said.
Mr Beedell, 31, a youth pastor who lives locally, said he visited the bank with a friend to pay in money raised by Ashford Baptist Church to pay for a new building.
The gunman entered the bank wearing a white boilersuit and dust mask, shouting "Everyone get down on the floor", Mr Beedell said.
The man asked whether anyone had a heart condition and "some people" then left the bank.
Mr Beedell said: "He started shouting at people. He threw a lot of boilersuits out so we would look like him.
"I managed to get half of my boilersuit over my head. He came up behind me and put the gun back to my head and said 'Put it on'. The most bizarre thing was that it suddenly seemed to fit.
"Then he wanted money and was obviously threatening people."
He added: "Although we were scared the bank manager was incredibly calm, the staff were incredibly calm and I guess I was calm as well. When he had the gun at the back of my head, I wasn't panicking, I wasn't thinking I'm going to die."
The sound of police helicopters was audible within 10 minutes of the gunman entering the bank, he said.
The man was "clicking the gun every 20 to 25 seconds.
"I guess that's possibly why I didn't feel quite so scared. I just couldn't work out where those cartridges in this gun were going."
At one point the man offered the hostages cigarettes and alcohol because he wanted them to be "calm and relaxed" but he could not find his lighter.
After around three hours, the man asked the bank manager to open the doors and some hostages were let out.
Mr Beedell, who was wearing a boilersuit, said: "The armed officers didn't know who I was - I was cuffed and I fully understand the reasons for that. Actually I thought the police handled it well."
He added: "Although it was a tough and traumatic experience, no-one was physically hurt and each of us get to get on with our lives."
Meanwhile, others caught up in the siege told of their ordeals.
Angela Vaughan, 46, who walked into the bank with her six-year-old Joseph, told The Sun: "The gunman looked at Joseph, pointed his gun, and said, 'Get out of here little boy'. Joseph froze. I quickly grabbed my son and dragged him out."
And Josh Williams, 20, told the paper: "We heard police cars screeching down the road. The cops jumped out with their guns and got behind their cars."
A hostage named Lianne told the Daily Telegraph she was inside the bank when a man came in and told people to get down.
But she said she was allowed out after suffering a panic attack.
"He handed out white boiler suits to staff members and told them to spray paint the windows," she said.
"I started to have an anxiety attack and the man asked if anyone suffers from heart problems to tell him. I told him I suffered from anxiety attacks and he let me go."
Supt Duncan Greenhalgh from Surrey Police said: "Shortly before 4pm, Surrey Police received reports that a man with a firearm had entered Barclays Bank in Church Road, Ashford.
"A number of people were inside the bank at the time and being prevented from leaving.
"This was a fast-moving incident and police were on the scene within minutes.
"Trained hostage negotiators made contact with an individual inside the bank and just after 7pm a man came out of the bank and was contained by armed police.
"A man in his 30s has been arrested and is currently in police custody. All the people involved are being assessed by medical teams but there have been no serious injuries.
"This was obviously a very traumatic experience for those members of the public and bank staff caught up in it but I am extremely pleased with the quick and effective response from officers who brought this situation to a close without injury to anyone, including the suspect.
"I would like to thank the community of Ashford for their understanding whilst we dealt with this incident. Police will remain here for some time gathering evidence but we will try and keep disruption to a minimum."
Tim Kiy, Barclays corporate affairs director, said: "We are immensely relieved and happy that all those involved are now safe and able to be reunited with their families.
"Our focus now is the wellbeing of those involved, who will be provided with all the support and counselling they need.
"We would like to thank the Surrey Police for their role in the swift and successful outcome."