A broadcast by People's Community Radio Link (PCRL) in February 2002 forced engineers to shut down one of West Midlands Fire Service's major radio links, Birmingham Crown Court heard on Thursday.

PCRL's occupation of the airwaves allegedly made messages between fire crews and controllers "unintelligible".

Cecil Morris, who is said to have run PCRL from a Birmingham flower shop since 1985, denies conspiracy to manage, finance and operate an unauthorised broadcasting station.

The main fire control had no effective communication from south Birmingham sweeping west up to Wolverhampton Peter Woodhead West Midlands Fire Service

In a prosecution brought by the new telecommunications watchdog Ofcom, Mr Morris, 57, of Dudley Road, Winson Green, Birmingham, also denies a further count of conspiracy to use wireless telegraphy contrary to the Criminal Law Act and Wireless Telegraphy Act.

Peter Woodhead, the fire service's senior radio engineer, said he was called to the main control room on 8 February, 2002, because the airwaves had been "totally swamped" by PCRL's broadcasts.

The court was told he was forced to shut down the link based at Romsley, north Worcestershire, which serves an area of 360 square miles.

In a statement, Mr Woodhead said: "The main fire control had no effective communication from south Birmingham, sweeping west up to Wolverhampton, apart from cellular coverage, which is not deemed an acceptable alternative."

Normal service was resumed several hours later after radio enforcement officials managed to shut down the station.

Life-threatening activity

William Rickarby, prosecuting, described Mr Morris, who broadcasts under the name "The Music Master", as the prime mover in the operation.

Mr Rickarby told the court that broadcasters such as PCRL endangered the emergency services and aviation industry by interfering with their bands.

He added that they also deprived the taxpayer of revenue and performers of their royalties.

Mr Rickarby told the court: "Pirate radio can cause a real risk of danger to life because of the interference with civil aviation bands and emergency services as well."