At least 40 people were killed Sunday night when supporters of a local football team clashed with Cairo police before a Premier League match. In response to the attack, the government suspended the Egyptian Premier League indefinitely, and the country’s public prosecutor ordered an investigation. According to the Egyptian interior ministry, the clashes occurred when Ultra White Knights boosters attempted to enter the army-owned stadium without buying tickets. Witnesses said police tried to set up barricades and fired tear gas on the throngs of supporters. “The police were in front and behind the gate. They fired tear gas,” said one witness. “This caused panic and people fell on top of each other. We started to leave quickly. There were old people in the crowd and they were crushed by other fans.” It was the deadliest incident of sports stadium violence since riots in Port Said in 2012 killed more than 70 people and injured hundreds more.