"The Egyptian authorities must immediately order an independent and impartial investigation into the killing of the four men, and send a clear message that carrying out attacks and inciting violence against Shiite Muslims will not be tolerated," AI Deputy Director of Middle East Programs Hassiba Hadj Sahraoui said.
Amnesty said villagers in south Cairo stormed the house of a local Shiite villager, stabbing the residents. Witnesses told the advocacy group the perpetrators were chanting anti-Shiite slogans during the Sunday raid.
"Investigations must look at why security forces yet again failed to stop the bloodshed, as well as whether advocacy of hatred and incitement to violence played a role," Sahraoui said in a Monday statement.
AI said it was frustrated with Morsi's administration for hosting Sunni supporters of the Syrian opposition who allegedly used anti-Shiite propaganda during a conference in Cairo in mid-June.
Morsi, a Sunni, issued a statement Monday condemning the weekend attacks but failed to criticize the persecution of Shiites.
AI said Egyptian authorities issued 15 arrest warrants following the raid, though no arrests have been made.
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