Detectives have arrested a second man over a high street bank bomb alert which sparked a three-hour stand-off with armed police.
The unemployed 23-year-old from Luton, Beds, was held last night on suspicion of conspiracy to steal in connection with the incident at the Co-operative Bank in Watford yesterday, Hertfordshire Police said.
Police also confirmed that another 23-year-old man from Luton arrested straight after the scare was a Co-operative Bank employee.
Officers are continuing to question him on suspicion of conspiracy to steal.
Watford town centre was brought to a standstill when a man walked into the bank on Market Street at about 10am yesterday, allegedly claiming to be carrying a bomb and threatening to blow up the building.
Armed police and military bomb disposal experts attended the siege before he gave himself up.
Tests later revealed that the man's device was harmless and police stressed there was no suggestion that the incident was linked to terrorist activity.
Witnesses described police marksmen aiming their guns at the bank and reported rumours that the man had a bomb strapped to his body.
One unsuspecting pensioner even tried to enter the branch during the alert.
Ron Miller, co-owner of Beatrice Bray florists, directly opposite the bank, watched events unfold from outside his shop for 30 minutes before he and his staff were evacuated.
Mr Miller said: "I saw an elderly gentleman trying to push the door to go in. Someone further down the road screamed: 'Don't go in there'. He just walked away."
He added: "The police had cordoned off both ends of the road by then. If there had been a serious threat, we would have been in real trouble. The bank is only 30ft away."
Other witnesses said they saw bank staff crying outside after the incident was brought to a close.
Ryan Saunders, 22, who was on his way to work at nearby Bhs at the time, said: "There were lots of people panicking, and then I saw the bomb disposal van speed past me. Everyone was desperate to get away."