The 'Mona Lisa of pigeons' is among five racing birds valued £625,000 stolen by gang - as the sport is rocked by 'explosion' of thefts

The 'Mona Lisa of pigeons' is among five racing birds worth £625,000 stolen by a gang amid a recent 'explosion' of thefts in Belgium.

Champion pigeon racer Tom Van Gaver was shocked when he walked into one of his aviaries last November to find part of the door had been smashed from the inside.

He soon realised several of his birds were missing, including Finn, one of his most renowned breeders. 

Father and grandfather to many champions, Finn was 'the Mona Lisa of the pigeon world', Van Gaver told The Guardian.

CCTV footage shows a masked raider snatching the startled bird before bundling him into a bag.

Although the theft left Mr Van Gaver 'sad and upset' there was no time to wallow in misery as he had to fix the weak point in his security system before the thieves could strike again.

With cameras, locks, and sensors already in place Mr Van Gaver had thought he had all bases covered.

But he had not bargained on the criminals breaking in through a loft roof, having chopped down hedges in his neighbours' gardens to reach his property.

Beefed-up security now means Mr Van Gaver's home is separated with a fence bearing laser sensors and cameras. 

'It is like a prison in my garden,' he said.

The theft of Van Gaver's pigeons is only one of the latest to rock the pigeon racing community in Belgium - which is renowned as the birthplace of the sport.

Patrick Marsille, secretary general of the Royal Belgian Pigeon Federation said: 'The problem has always existed … but in the last year it has exploded'.

'Not a week goes by without a theft somewhere,' Pascal Bodengien, head of the Belgian Pigeon Racing Federation concurred.

The association estimated that up to 15 thefts had taken place between October and mid February, with an estimated 500 birds stolen. 

Mr Marsille believes calculated criminal enterprises from eastern Europe target particular birds or owners, hoping to steal champions to breed their offspring.

Once described as the horse racing of the poor, pigeon racing began in the coal-mining region around Liège in 19th-century Belgium, reaching its heyday after the second world war, with about 200,000 fanciers in 1950. 

These days there is far less interest in the hobby and animal welfare activists and ethicists have criticised the sport for the stress imposed on birds in gruelling long-distance competitions.

The Belgian Pigeon Federation says it requires its members to make the wellbeing of their animals a priority. 

A typical competition would see pigeons released from one spot and fly back to their lofts, covering hundreds of kilometres. 

The winner is the fastest bird, measured in metres per minute, using an ankle tag linked to a loft sensor.