A middle-aged white man charged with the killing of three American Muslim students in Chapel Hill, North Carolina, in February, shot the victims in the head, autopsy reports reveal.

Craig Hicks shot dead Deah Shaddy Barakat, 23, his wife Yusor Mohammad Abu-Salha, 21, and her sister, Razan Mohammad Abu-Salha, 19, near the University of North Carolina at Chapel Hill campus on February 10, 2015.

According to autopsies released on Wednesday, Barakat was shot multiple times in the head and chest after he answered the door to his apartment.

Barakat’s wife and her sister were also both shot in the head.

Namee Barakat and his wife Layla Barakat, parents of shooting victim Deah Shaddy Barakat, react as a video is played during a vigil on the campus of the University of North Carolina in Chapel Hill, North Carolina on Feb. 11, 2015.

According to the autopsies, the women died of contact wounds to the head, indicating the gun was very close or against their heads.

The autopsies show the shooter was standing over the women when he fired the shots because Yusor was shot in the top of the head, her sister was shot in the upper back of the head, and the bullets traveled downward.

Craig Stephen Hicks, 46, enters the Durham County courtroom, Feb. 11, 2015, in Durham, North Carolina, the US.

Last month, a judge ruled that prosecution could plead for the death penalty against Hicks, who is charged with three counts of first-degree murder.

The 46-year-old is being held at a prison in Raleigh, North Carolina, waiting for his trial.

In February, local police launched a homicide investigation focusing on a dispute over a parking space, but the families rejected that narrative, describing the killing an “execution-style murder” and a “hate crime”.

The tragic murders of three bright Muslim students started a debate over whether the students were targeted because of their religion.

A man holds a placard during a vigil for three young Muslims killed in Chapel Hill, North Carolina, at Dupont Circle on February 12, 2015 in Washington, DC.

The incident also caused outrage among Muslims all over the world who called for the shooter to be charged with hate crimes.

There is a high probability that the shooter targeted the victims because of their religion and national origin, the American-Arab Anti-Discrimination Committee has said.