A court in the United States on Monday sentenced a gunman, identified as Ahmad Al Aliwi Alissa, to life in jail for fatally shooting 10 people at King Soopers supermarket in Boulder, Colorado, on March 22, 2021.

The convict’s unanimous guilty verdict by the jury came about six hours over two days before Judge Ingrid S. Bakke found Mr Alissa, who has been in custody since the shooting at the grocery store, guilty of murder.

The lawyers of the now 25-year-old convict, who was diagnosed with schizophrenia after the attack, admitted their client carried out the shooting but insisted he was unwell and that mental illness aided his action, making him unable to know what he was doing was wrong.

Despite about two weeks of testimony that centred on the mindset of Mr Alissa at the time he launched the attack, the jury dismissed his lawyers’ argument.

Following 10 convictions of first-degree murder, including the murder of a police officer, Judge Bakke, gave a guilty verdict with 10 consecutive life sentences, excluding the possibility of parole.

The victims of his attack at the store were the first police officers to arrive at the scene, store employees and shoppers, who were between 20 and 65.

The attack at the grocery store happened days after a separate mass shooting took place in Atlanta.