Italy's embassy in Egypt tweeted condolences to the families of victims of an explosion outside the National Cancer Institute in central Cairo that killed at least 20 people and injured nearly 50 early on Monday.
"The Italian Embassy in Cairo offers its deepest condolences to the families of those who lost their lives in the explosion outside the Cancer Hospital last night. Our thoughts go also to those who were wounded. We wish them a speedy recovery," read the tweet.
Egypt's interior ministry said that terrorist group Hasm, a violent offshoot of the banned Muslim Brotherhood, was behind the blast which happened at midnight. An alleged Hasm member has been arrested over the explosion, according to the ministry.
The explosives-laden car was on its way to stage "an act of terrorism" when it drove into other cars, triggering the blast outside the hospital, although the planned target was unclear, the ministry said.
The country's public prosecutor has opened an investigation.
Part of the Italian consulate in Cairo was destroyed by a car bomb in 2015 - one of a series of violent explosions by suspected Islamists that shook the Egyptian capital that year.