A student who waited for his housemate in hiding before stabbing him has admitted to killing him.

Jamie Collins, 21, died in the garden of the home he shared with housemate Zack Coughlan, 23, in Filton, South Gloucestershire.

The robotics student at UWE Bristol was ambushed in the alleyway and stabbed repeatedly on the evening of April 8 by Coughlan, dressed in all-black and wearing a mask.

The attack, described as a ‘carefully planned and cold-blooded execution’ by the prosecution, was caught on CCTV, which Mr Collins’s brazen killer showed to the police after they arrived.

Bristol Crown Court heard how Coughlan left him dying outside at about 6pm as he cycled away on his housemate’s bike.

Coughlan, also a robotics student, had first denied the murder charge before changing his plea to guilty today.

It comes after Mr Justice Linden ruled that Coughlan’s partial defence of manslaughter by reason of loss of control could not be left to the jury to consider as part of their murder charge deliberations.

The two students lived in the £300,000 three-bedroom house owned by Coughlan, and were both in their final year.

After cycling away from the crime scene, Coughlan dumped the ride at a retail park and bought a change of clothes.

His bloodstained clothes were stuffed into bags weighed down with bricks before he threw them into a pond.

He returned to the shared house on Cleve Road at about 9pm, where he popped a pizza in the oven before gaming with friends.

Eventually at about 2am, he called 999 claiming he just discovered his housemate in the rear garden.

The 23-year-old was first treated as a witness before detectives found his blood on Mr Collins’s bike, and his mobile phone data matched the killer’s movements.

Clothes recovered from the lake were found containing blood and Coughlan’s DNA.

The brazen killer told a university friend he wanted to organise a memorial for Mr Collins after the murder.

The student’s family described him as a ‘caring young man’ who was deeply passionate about equality and that ‘his unapologetic inclusivity will be his legacy for all of us.’

He was just two pieces of coursework away from graduating at the time of his death.

The family said: ‘Our family has been sickened that Zack Coughlan pretended to help Jamie when in fact he is responsible for killing him.

‘We even felt sympathy for Zack at the start, and asked police if he was okay, because of how he had initially deceived everyone.’

Coughlan will be sentenced tomorrow morning.

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