Passers by and police were among at least 30 people injured when migrants staged an angry protest near the southern Italian city of Bari.
Frustrated at delays in processing their asylum applications, some demonstrators hurled stones while others blocked a road and a railway line, setting fire to piles of rubbish and tyres.
Regional and local officials later held discussions with immigrants’ representatives and will have further talks about their grievances on Wednesday.
Immigration, especially from Africa and Eastern Europe, is a sensitive issue in Italy and protests by immigrants kept in holding centres across the country occur sporadically.
Long-simmering tensions have risen to the fore in recent years after Prime Minister Silvio Berlusconi’s conservative government cracked down on illegal immigration and tightened procedures for obtaining legal residence in the country.