Egypt's Interior Ministry said police killed a senior Muslim Brotherhood leader and another member of the group in a shoot-out in the capital Cairo - a version of events contested by the group.
A ministry statement carried by the state MENA news agency on Tuesday said Mohamed Kamal, 61, was killed in an exchange of gunfire along with Yasser Shahata Ali Ragab as police tried to arrest them at an apartment in Bassateen neighbourhood.
Sources in the Muslim Brotherhood, though, told Al Jazeera that security forces killed two of its leaders hours after detaining them.
The ministry accused Kamal of running armed branches of the group. But the Arab world’s oldest Islamist organisation insists it is committed to peaceful activism.
Kamal was twice sentenced in absentia to life in prison on charges of setting up an armed group and setting off an explosion near a police station, while Ragab was sentenced in absentia to 10 years in jail.
The government of President Abdel Fatah el-Sisi has outlawed the group and cracked down harshly on its members since toppling Mohamed Morsi, the country’s first democratically elected president, in 2013.
Thousands of the group's members, including its top leadership, have been jailed for opposing the coup.
Kamal was one of the most prominent leaders of the Muslim Brotherhood and a member of the Guidance Bureau. He was previously in charge of the supreme Administrative Committee, known as the youth committee.
Source: Al Jazeera News Agencies