A university student allegedly waited to ambush his housemate and stab him 30 times, a court has heard.

Zack Coughlan, 23, dressed all in black and wore a mask and gloves when he allegedly ambushed Jamie Collins, 21, in the garden of their home in Filton, South Gloucestershire.

Bristol Crown Court heard Jamie was stabbed repeatedly and Coughlan left him dying in the alleyway as he cycled away.

Jamie was attacked shortly before 6pm on April 8 after returning from the University of the West of England (UWE) Bristol, where he was studying robotics alongside his alleged killer.

Coughlan is then thought to have dumped the bike at a nearby retail park where he bought a change of clothes and threw his bloodstained clothing in a pond, the court heard.

He then returned home to the house they shared in Cleve Road at about 9pm, put a pizza in the oven and did some online gaming with friends.

Adam Vaitilingam KC, prosecuting, told the jury: ‘A few hours later he decided it was time to call the police and pretend that he had just found his friend’s body in the garden.

‘At about 2am – eight hours later – the defendant called 999. He said that his friend had been stabbed. They told him to do CPR until paramedics arrived, and he told them that he was.

‘Shortly afterwards, armed police officers arrived. They saw Jamie’s body in the back garden of the house. They spoke to the defendant. He told them that he had been out at the park, and he had just come home.

‘He had noticed that the back gate was open so came outside, and it was then that he found Jamie lying in the garden.’

The court heard the alleged attack was caught on CCTV installed at the shared house, which Coughlan showed to officers who initially treated him as a witness.

Mr Vaitilingam told jurors it was the prosecution case that the masked attacker was Coughlan.

He said the defendant’s blood had been found on Jamie’s bike, and analysis of his mobile phone matched the killer’s movements captured on CCTV following Jamie’s death.

‘The investigation showed clear evidence that it was Zack who had been the man who had waited for Jamie and then stabbed him to death before cycling away,’ he said.

‘And so Zack went from being a witness to a suspect in the murder. He was arrested and interviewed by the police.’

Coughlan had injuries to his hands, and he told people who saw him bleeding that he had been climbing trees and had fallen and hurt himself.

The jury was told that Coughlan and Jamie were both final year students at UWE Bristol and lived together in a house owned by the defendant.

There were no ‘significant’ problems noticed by the pair’s friends, who said they hung out often and went out together.

The court heard that Coughlan now accepts he had killed Jamie. Coughlan, of Cleve Road, Filton, South Gloucestershire, denies murder.

The trial continues.

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