The incident took place at TSB in Clerk Street, Edinburgh around 1.30pm on Monday.
A man entered the bank and approached a bank teller before removing an item from a holdall, which he implied was an explosive that he would detonate, and demanding money.
Officers were quickly made aware and the man fled, leaving the area in a taxi. He left the device behind, which was swiftly assessed to be a hoax that posed no risk whatsoever to the public.
The suspect is described as being white with tanned skin, of heavy build with a full face, 5ft 8 - 10ins tall, aged 60 to 70 years old, wearing large dark-rimmed glasses and possibly spoke with a Russian accent.
At the time of the incident, he was wearing a black furry beanie hat, a black 3/4 length woollen coat, black trousers, black leather shoes and carrying a black holdall.
Prior to this, he is believed to have got into a taxi in Frederick Street at 12.45pm. He then travelled to various banks in the city centre, before travelling to Clerk Street where the taxi waited.
He returned to the taxi and was dropped off at Waverley Station.
Enquiries carried out with the British Transport Police have established that the suspect boarded the 14:19 train to Manchester Piccadilly, having arrived in Edinburgh at 12:14 that afternoon on the London Kings Cross train.
Detective Inspector Grant Johnston of Gayfield CID said: “We are continuing enquiries with our colleagues in the British Transport Police to establish the suspect’s movements prior to arriving in Edinburgh, and after his departure on the Manchester bound train.
“I believe the suspect may be a regular visitor to Edinburgh and, as part of the ongoing investigation, I’d urge anyone who may have seen the man described in the city centre on Monday or in recent weeks, or who recognises his description, to contact us immediately.”
Anyone with information which may be relevant can call Police Scotland via 101, quoting incident number 1592 of 7th January, or report this to the charity Crimestoppers anonymously on 0800 555 111.
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