Soldiers on Olympic security watch in a residential Collier Row block found themselves dealing with a different sort of house when they happened upon a “gang of young men” from an illegal dance music radio station.

The men were trying to break into the roof area of Highfield Tower to set up broadcasting equipment.

But they failed to pick up signals that the tower had been turned into a military surveillance base by a group of Ministry of Defence (MOD) personnel during the Games.

Details of the confrontation came to light following last week’s full council meeting, in answer to a written question from Rainham and Wennington councillor David Durant.

For the soldiers it was a case of the beat goes on – they had already shut down the station once during the exercise.

Cllr Lesley Kelly, cabinet member for housing, said: “The only event of interest [during the training exercise undertaken in May] is that the MOD were able to prevent a gang of young men breaking into the roof space, who were intent on restoring their pirate radio signal station, which had been removed by the military.”

A spokesman from broadcasting watchdog Ofcom said the frequency being used was 106.5 FM. Pirate station Project FM, which broadcasts on this frequency, has used the tower block in recent months - but Ofcom was unable to confirm which station had been broadcasting when the MOD intervened.

A Project FM spokesman denied the station had been involved.

The Ofcom spokesman added: “People often set up pirate signals in high-rise tower blocks. There have been a few cases about this particular station since the end of last year.”

Ofcom has so far intervened in Project FM three times – but because the broadcasting antenna is usually in a separate place from the studio, pirate stations are often hard to shut down on anything other than a temporary basis.

Project FM describes itself on Twitter as “London’s Leading Underground House Music Station”. The website contains a petition to “help Project Live get a legal licence for broadcasting” that has so far been signed by 156 people.

The Ofcom spokesman added there were “several hundred” pirate stations active in the London area. Unlicensed radio signals trespass on precious bandwidth allocated to other stations, and can block the emergency services’ communications.

But despite interference from the soldiers, the broadcasters have yet to face the music – Havering police said they hadn’t been made aware of the incident.