Egypt hangs five prisoners despite human rights concerns
The hangings came days after the execution of 15 inmates convicted of attacking police and the military in the largest mass execution in Egypt in recent memory.
Seven Egyptian rights groups condemned the hangings, claiming legal procedures against them were flawed and at least one of the 15 appeared to have been tortured in detention.
They also said relatives were not allowed to see them on the day of their execution, as the law requires.
Four of those executed on Tuesday had been sentenced to death by a military court over a 2015 the bombing at a stadium north of Cairo that killed three military cadets.
The fifth had been sentenced to death over a criminal matter, security officials said without elaborating.
The other four had been accused of having links with the Muslim Brotherhood movement of former president Mohamed Morsi whom the army toppled in 2013 following protests against his single year in office.
On December 26, prison authorities hanged 15 inmates sentenced to death by a military court over attacks on the police and military in the Sinai Peninsula.
Attacks by jihadists in the restive peninsula have killed hundreds of policemen and soldiers since Morsi's overthrow.
Courts have since sentenced hundreds of Islamists to death, although most have appealed the rulings and won retrials.