CAIRO - An Egyptian criminal court on Monday acquitted an Irish-Egyptian who has been detained for four years on a slew of charges, including murder, arson and illegal possession of weapons, his defence lawyer said. However, the court sentenced an American-Egyptian to five years imprisonment over the same charges.

Yasmeen Said said Ibrahim Halawa has yet to be released following the verdict by the criminal court in a case involving nearly 500 defendants. The completion of his release paperwork could take hours or a few days.

Irish Foreign Affairs Minister Simon Coveney welcomed Halawa's acquittal. "Ibrahim Halawa's name has been cleared and his innocence is confirmed. I look forward to him being released from custody without delay," he said in a statement posted on his social media accounts.

"The Government's priority now is to support Ibrahim and his family in every way that we can in order to ensure that Ibrahim is able to return home to his family and friends as soon as possible," he added.

Halawa is the son of a senior member of the Muslim Brotherhood, an Islamist group that swept to power in elections after the 2011 uprising but was later outlawed as a terrorist organization in Egypt.

He was arrested along with his three sisters in August 2013, days after security forces violently broke up a sit-in by supporters of Islamist President Mohammed Morsi, who had been overthrown by the military the previous month. The sisters were released in November 2013 and have since left Egypt.

Monday's verdict acquitted the sisters, along with 48 other defendants. Of the case's 493 defendants, 43 were sentenced to life in prison, including the father of Mohamed Sultan, the Egyptian-American former detainee and hunger striker. The rest received jail sentences of between five and 15 years, including an American-Egyptian named Ahmed Eitwy. Twenty-one of those receiving life sentences are at large and were tried in absentia.

Halawa's family watched the verdict live online from their home in Dublin, Ibrahim's sister, Somaia, said.

"We were very delighted. We couldn't believe it when the judge acquitted Ibrahim. After all this suffering, it's really coming to an end," she told The Associated Press.

She said that Coveney called the family to congratulate them. She added that the family doesn't know when he'll be released.

Amnesty International also welcomed the verdict on Halawa, but questioned the fairness of a mass trial. "We hope he will soon be reunited with his family in Ireland," their statement said.

Mass trials of Islamists have been common in Egypt since the 2013 ouster of Morsi, with several cases involving hundreds of defendants and ending with mass death sentences, most of them passed against defendants at large or overturned on appeal.

Halawa was 17 when he was arrested on Aug. 16, 2013 — a day of violence centred around a mosque in Cairo's central Ramses square. Forty-four people were killed and nearly 60 injured in clashes between Morsi supporters and police that day.

News from © The Associated Press, 2017