Twenty-two people were killed outside an Egyptian football stadium on Sunday when security forces barred fans from entering, the public prosecutor's office said.
Most of the dead were suffocated when the crowd stampeded after police used tear gas to clear the fans trying to force their way into a league match between two Cairo clubs, Zamalek and Enppi, doctors and witnesses said.
A health ministry spokesman told Reuters by phone the final toll was 19 dead and 20 injured. The reason for the discrepancy in numbers between the health ministry and the public prosecutor's office was not immediately clear.
Football matches are often a flashpoint for violence in Egypt where 72 fans were killed at a match in Port Said in February 2012. Since then Egypt has curbed the number of people allowed to attend, and supporters have often tried to storm stadiums they are banned from entering.
Outside the Cairo hospital treating the injured, scores of youths wearing Zamalek T-shirts appeared shocked as families arrived to see if their relatives were safe.
One mother cried and shouted when she found the name of her son on a list of the dead posted by hospital staff.
"I'd told him: leave football matches," she said.
Relations between security forces and fan groups known as Ultras have been tense since the 2011 popular uprising that ended the rule of autocrat Hosni Mubarak, in which the Ultras played a key role.
"Huge numbers of Zamalek club fans came to Air Defense Stadium to attend the match … and tried to storm the stadium gates by force, which prompted the troops to prevent them from continuing the assault," the interior ministry said.
The public prosecution ordered the arrest of the leaders of the Zamalek supporters group, Ultras White Knights, after Sunday's incident, official media reported.
On their Facebook page, the Ultras White Knights described the 22 dead as "martyrs" and accused security forces of a "massacre".
Despite the violence, the match went ahead and ended with a 1-1 draw.
The Egyptian Football Federation said it had reversed an earlier decision to allow fans to return to the stadiums by the start of the second half of the season. The original decision had been taken only a few days ago.
Shortly after that, the Cabinet said in a statement that the national league championship would be postponed indefinitely.