Police said three brothers and a sister, aged from 4 to 11, died when a fire destroyed their wood shack on Rome’s outskirts on Sunday night while their mother was out buying food and other adult family members were fetching water.
The blaze was most likely caused by a burning ember from a wood stove the family used to keep warm, officials said.
The area had been occupied, razed and occupied again several times in recent years.
Mayor Gianni Alemanno blamed the bureaucracy, saying it was taking too much time to obtain all the required local permits to move the nomads to safer sites.
He said he would ask the national government for special powers to shut down illegal sites and move the nomads to approved locations.
Roma, who come mainly from European Union members Romania and Bulgaria, make up many of the people who enter Italy each year. Most do not integrate and many beg on street corners or wash car windows for change.
The European Commission rebuked France last year for expelling more than 8,000 Roma.
