Egyptian prosecutors said Tuesday that the banned Muslim Brotherhood was behind the deaths of 21 football fans at a Cairo stadium last month.

Prosecutors sent 16 alleged members of the Brotherhood and of the Zamalek football team’s White Knights fan club to trial on charges of murder, thuggery and destroying property.

The deaths occurred after police fired tear gas into crowds of Zamalek fans seeking to gain entry to the match at the Air Defence Stadium on the outskirts of Cairo on February 8.

Would-be attendees were funnelled into a makeshift iron cage surrounded by barbed wire, and, according to witness reports in the local press, were crushed by the crowds arriving behind them.

Video shared on social media after the disaster showed trapped fans who appeared to be shouting “we’re dying,” while others leaped on top of the cage.

As the cage collapsed, at least one policeman opened fire from a type of shotgun used for teargas and birdshot. More teargas rounds followed, sending the packed crowds stampeding.

Official forensic reports said that the fans had died of injuries due to the crushing stampede, although a forensic official earlier said that asphyxiation from tear gas was also a factor in the deaths.

An Amnesty International report said that police, unable to hold back pushing crowds, started beating fans and then shot tear gas horizontally into them.

Tuesday’s prosecution statement said that the Muslim Brotherhood had provided funds and explosives to members of the White Knights group to bring about a riot.

Prosecutors said that the White Knights members had set off fireworks at police, causing several injuries, and chanted insults against them, leading to the police response that caused the stampede.

The Islamists hoped that a riot at the match would lead to the failure of a high profile investment conference that was held this weekend, the statement said.

Prosecutors also referred a police officer to trial on charges of shooting a young socialist activist dead in Cairo in January.

Shaimaa al-Sabbagh was shot in Cairo’s central Talaat Harb Square on the eve of the anniversary of the 2011 revolution against long time leader Hosny Mubarak.

She was taking part in a small procession organized by the Popular Socialist Alliance party to lay a wreath on a memorial to the martyrs of the revolution in Tahrir Square.

Party members and leaders who participated in the procession are also to face trial on charges of holding an unauthorized protest and disturbing security, the prosecution said.

The party on Saturday accused police of storming and ransacking its offices in Alexandria. The Interior Ministry denied the accusation.

Under a law passed in November 2013, a few months after then army chief Abdel-Fattah al-Sissi ousted Islamist president Mohammed Morsi, protests are effectively banned without police authorization.

Amnesty International said in February that at least 1,400 protesters had been killed in excessive use of force by security forces since Morsi’s ouster, without any security officers being held accountable.

Authorities have accused demonstrators of initiating violence in many of those cases. SAPA