THE boss of a G4S cash depot told a court he felt "terrified" when he received a letter threatening to detonate bombs under workers' cars if he did not pay out £1m.

Employee Daniel Garland, 19, of Durham Place, Chester-le-Street, has admitted a bomb hoax but denies blackmailing the security giant by sending the anonymous letter to the general manager of the site in Thornaby, Teesside, in January.

Teesside Crown Court heard how the teenager threatened to blow up vehicles, storm the depot with weapons and visit a mother and her baby while her partner - a G4S employee - was at work.

The depot's general manager Dean Jeffels told the court: "Going through this letter again today is terrifying."

The police were informed and a major investigation was launched, led by a chief superintendent.

Vehicles were brought back to the depot for checking by sniffer dogs and specialist teams, while the depot's 134 employees on duty that day were prevented from going home.

Police believed from the level of information in the letter that an employee was the author, and they identified Garland as a suspect.

After his arrest they found a spare copy of the letter hidden behind a poster in the music room of his home, the jury heard.

Paul Rooney, prosecuting, said: "This case concerns a letter which was sent by the defendant Daniel Garland to his employers G4S.

"In the letter he demands £1m from them and makes threats to cause explosions and he infers he will cause harm to a newborn baby and her mother if his demands are not met."

A G4S van was robbed in December last year in Middlesbrough and the raiders who got away with a substantial amount of cash have not been caught, the jury heard.

The author claimed responsibility for the raid, named two employees as being "inside men" and said they had been paid so much for their information that he now required a further £1m, Mr Rooney told the court.

He wanted the cash to be loaded into a red Volvo lorry that would be parked outside the depot the next day.

Mr Rooney said: "The letter went on to state he fitted mini bombs to a number of G4S vehicles as well as employees' vehicles.

"It was indicated these bombs could be detonated by remote control."

The prosecution said Garland referred to an employee who had just returned to work after the birth of his baby, leaving his partner alone during working hours.

Mr Rooney said: "If payment was not made then the author of the letter and others would be paying them a visit while they were alone."

The message also stated the robbers would be heavily armed and were not "scared" to force their way into the depot if £1 million in notes was not there for them.

Mr Rooney said: "It was reiterated that failure to load £1m into the lorry, or if the police were present, would result in the bombs being detonated.

"This was blackmail, say the Crown."

Mr Jeffels said G4S activity from the depot was "stopped dead" that day.

Nicole Horton, defending, asked him what he thought of Garland. The boss replied: "I thought he was a nice lad. I actually thought he had a bright future with G4S."

Security manager Christopher Wilcox said Garland worked in the "coin cage".

He said he had shouted at the teenager when £13,000 went missing - although there was no suggestion the money had been stolen, and it was later accounted for.

Although he had told him off in front of others, Mr Wilcox did not apologise when the money was accounted for, the jury heard.

Miss Harton asked: "Did you feel you handled it particularly well?"

Mr Wilcox replied: "Probably not."

Garland denies two counts of blackmail.

The trial continues.