A 14-year-old boy was pinned to the ground and hacked to death with a machete at a Wyoming mall while trying to protect his girlfriend.

A teenager was held to the ground and stabbed to death by two attackers wearing ski masks as he tried to protect his girlfriend at a Wyoming shopping centre, a court has heard.

Dominique Antonio Richard Harris and Jarreth Plunkett, both 15, are accused of killing Bobby Maher, 14, in the fatal attack at Eastridge Mall in Casper in April, according to the Cowboy State Daily.

Harris has pleaded not guilty to conspiracy to commit first-degree murder in connection with the attack. He is being tried as an adult and reportedly admitted to police that he held Maher down to help Plunkett in the alleged attack.

The teen told investigators he did not know Plunkett was going to kill Maher and claimed he was restraining the teen only to “make sure the fight was over.”

However, surveillance footage of the April 7 attack shows him throwing Maher to the ground, then holding him down while Plunkett plunged a knife into the teen twice.

Police say Maher went to the mall to help his girlfriend, Haley Bressler, after she called him and said Plunkett and Harris were stalking her and a friend.

Surveillance footage taken from the mall shows Maher trying to escort his girlfriend and her friend out of the mall, but Plunkett and Harris stop them before they can leave.

Plunkett and Harris then confronted Maher because they were allegedly angry with the victim following an incident earlier this year at an Evansville park.

Harris told police that Maher asked the two 15-year-olds if they were “freaks” because he saw them leaving a portable toilet in the park together.

First responders were called to the scene of the stabbing and Maher was rushed to the hospital where he was pronounced dead. An autopsy showed he had suffered two stab wounds, including one that pierced his heart, the report said. Oil City News.

A witness told police they saw the two defendants pointing and laughing at the wounded and dying Maher before fleeing to the mall parking lot. They were arrested minutes later by a Natrona County sheriff’s deputy.

Bressler filmed the attack with his phone. The video was shown Thursday during the defendants’ preliminary hearing.

Harris was also charged with aggravated battery, assault and robbery for allegedly stealing a pair of knives — including the one used in the killing — from a Target store.

Harris’ defense attorney Brandon Booth said his client reserves the right to change his plea to mental illness or mental defect, even though he has already pleaded not guilty.

Harris told District Judge Kerri Johnson that he had never been diagnosed with any learning disability.

Plunkett also pleaded not guilty by reason of mental disease or defect. A judge ordered him to undergo a medical examination to determine his fitness to appear in court.

The law firm Fuller and Semerad, which represents Maher’s family, released a statement Thursday following the defendants’ preliminary hearing.

“The Maher family will fight to obtain justice for Bobby from all parties responsible for his murder,” attorney Ryan Semerad said in the statement.