The gang were reported to have made off with 300 gold and 200 silver items of jewellery, the cost of which is still being assessed.
The thieves appeared to have drawn their inspiration from the 'The Red-Headed League,' a popular Sherlock Holmes story that was first published in 1891, while the police said they were still trying to work out the value of what had been stolen.
In 'The Red-Headed League', rated by Conan Doyle as one of his best stories, a pair of robbers digs up the basement of a pawn broker's shop in 19th century London in order to break into a bank vault next door.
The thieves get the shop's red-haired owner out of their way by hiring him for an invented but well-paid clerical job. The owner is improbably told that only people with red hair are eligible to do the job. Holmes solves the bizarre case quickly, thwarting the theft by waiting for the thieves in the bank vault and catching them red-handed.
The Russian burglars hatched a similar albeit less complex plot.
"The criminals dismantled a brick wall in the flat and then got into the shop where they stole various adornments," said one police source.
They bought a flat located next to a jeweller's shop in St. Petersburg, Russia's second city, three weeks before the theft.
The flat shared a common wall with the jewellery shop next door, and neighbours said they thought nothing of it when they heard drilling and hammering, assuming that the flat's new owners were renovating the place.
The gang finally knocked a hole all the way through into the jewellery shop last weekend, triggering an alarm in the process. But the security guards who responded to the alarm twice assumed nothing was wrong as the doors and windows of the shop showed no signs of a break-in from the outside.
