Daesh (IS) militants have said they were behind a deadly explosion that severely damaged the Italian consulate in Egypt's capital, Cairo.
At least one person died and several people were injured when a car bomb went off at the building.
A tweet from a Twitter account linked to IS said Muslims should stay away from sites like the consulate, as they are "legitimate targets" for strikes.
Policemen and civilians were among the injured, the health ministry said.
The main entrance of the building was almost totally destroyed, windows were shattered and the building was flooded after water-pipes ruptured.
"Italy will not let itself be intimidated," the country's foreign minister Paolo Gentiloni said in a tweet, adding that there had been no Italian casualties.
Prime Minister Matteo Renzi spoke to Egyptian President Abdel Fattah al-Sisi after the attack and promised the two countries would stand together "in the fight against terrorism and fanaticism". Had it been a working day, the casualty numbers could have been much higher.
The attack raises questions about the security forces' ability to secure foreign diplomatic missions in the country, our correspondent adds.
Egypt's public prosecutor, Hisham Barakat, was killed last month by a car bomb attack in the city.
In the same month, another car bomb targeting a police station left three people dead.
Egyptian security forces have been battling Islamic militants, but the fighting has been mostly confined to the Sinai Peninsula.
Militants in Egypt have killed at least 600 police and armed forces personnel in the past two years.
The militants stepped up their attacks after the military overthrew Islamist President Mohammed Morsi in July 2013.
In recent weeks, Mr Sisi has promised to crack down further on Islamist militants.
Hundreds of Muslim Brotherhood members, including ousted President Mohammed Morsi, have been sentenced to death by Egypt's courts.
The majority remain on death row awaiting execution.