A teenager murdered a fellow teen in a “senseless” knife attack at a party which was advertised on Facebook, a court has heard.

Jay Whiston, 17, was stabbed on the night of September 8 2012, and died in hospital shortly afterwards.

Edward Redman, 18, denies murder.

The “unprovoked” stabbing was described as a “desperate example of the catastrophe and heartbreak” brought about by the use of knives, by prosecutor Mark Milliken-Smith QC during the opening of the trial at Chelmsford Crown Court.

“This is a case about the senseless and tragic taking of a young life so full of promise,” he told the jury.

Mr Milliken-Smith said the party where the stabbing took place was “advertised to friends via Facebook and by personal word of mouth” by the host.

The court heard that “numbers grew”, and some people, whose presence may not necessarily have been wanted at the party, were in attendance.

“Some of those who attended the party came from a distance and in groups,” the jury was told.

Mr Milliken-Smith said Mr Whiston arrived at about 8.30pm with a friend, adding that in the period leading up to the violence the party seemed to have various groups that “weren’t really mingling”.

Around 100 people were at the party, he added.

The jury heard that Redman and his group brought “an air of unease and tension”, and that they were “spreading an air of fear”.

They were slightly older than most of the people there and had been drinking earlier in the evening, the court heard.

Mr Milliken-Smith described how an incident broke out when one man was asked for his drink “with a tone”, down an alleyway near the house at Marlowe Way, Clacton, Essex.

Redman, of Halstead Road, Colchester, pushed the man who fell back and at this stage Redman punched him, it is alleged.

The man then handed the drink to Redman, and Mr Milliken-Smith said it would appear that Mr Whiston then stepped in and said: “We don’t want trouble.”

The prosecutor added: “Redman clearly did.”

Mr Whiston, of Aster Close, Clacton, was punched and then stabbed and, as he staggered away, Redman followed him, the court heard.

The jury was told Redman then said: “I’m going to do him.”

A bottle struck Mr Whiston’s head, and Redman stabbed him on his torso, before stabbing him again, the jury was told.

A 999 call was made by neighbours and a trauma team was waiting at hospital, but he was pronounced dead at 10.57pm, Mr Milliken-Smith said.

Redman, by now wearing no top and “realising exactly what he’d done” ran and fled, the prosecutor added.

Later that night, a taxi driver who was booked by Redman said that in the back seat he was “constantly receiving calls or texting”.

The jury was told that at one stage Redman said into his phone: “Just tell them there was a big fight. You don’t know anything about it.”

The taxi driver also said he heard “something about blood”.

Redman was taking the taxi to his girlfriend Shannon Fenlon’s house, the court heard.

Fenlon, 19, from Jameson Road, Clacton, is on trial accused of perverting the course of justice.

Redman’s father, Gary Redman, 51, and brother John Redman, 19, are also on trial accused of the same charge, and all three deny the charge.

A post-mortem showed that the fatal blow killing Mr Whiston was a stab wound to his heart.