A man who was part of a gang that terrorised a couple in a bungled robbery was identified after he left behind his fingerprint on a box of designer trainers.

Ex-university student Michael Sarpong had no explanation when confronted with the damning DNA evidence, but still maintained his innocence.

He was jailed for 13 years on Monday after a jury convicted him of robbery – involving a gun and a knife – on evidence described by a judge as overwhelming.

Matthew Roberts and his girlfriend Tierney Hodges were at home with friend Jade Casey when three men, two of whom were masked, burst in demanding to know where the safe was.

However, there was no safe in the house in Dongola Road, Strood, and they ended up stealing just a mobile phone, cash, a driving licence and a door key.

Prosecutor Craig Evans told Maidstone Crown Court there was a knock at the door in the early afternoon of August 30 2014.

As Mr Roberts opened the door the three men barged in and ordered him to sit down. They demanded: “Where’s the safe?” Mr Roberts suggested they had the wrong house.

One of the raiders told him: “Come on bruv, bullets don’t have eyes.” He then lifted his top and revealed the handle of a black handgun.

The two other men, one of whom was Sarpong, 26, went upstairs and into the kitchen to search for a safe.

Sarpong, who has a previous conviction for robbery, was not masked.

The other man continued to threaten the three victims. He pulled the gun out of his waistband and pointed it at Mr Roberts’ head.

He then went into the kitchen, picked up a knife and threatened: “Tell me where the safe is or I will kill you.”

He grabbed Miss Casey and Miss Tierney’s phones and some cash. When Mr Roberts refused to hand over his phone he was struck in the face with the knife handle.

He said of a dog in the house: “If she goes for me I will kill her.”

Mr Evans said police found Sarpong’s fingerprint on a box that had contained Ralph Lauren trainers. The two other men have not been caught.

Judge Martin Joy told Sarpong, of Drayton Avenue, Loughton, Essex: “This must have been an utterly terrifying experience for the victims.”

Because he spent 500 days on a tagged curfew, 250 will count towards the sentence.