Italian troops, some in body armour and with automatic weapons, were deployed on Monday on urban crime patrols, fulfilling an election campaign promise by Silvio Berlusconi, centre-right prime minister, to make Italy’s cities safer.

Immigrants hawking fake goods and a man who tried to rob an old woman were among the first to be detained near metro stations on the edge of Rome. Foreign embassies got extra protection, as did the square outside Milan’s famed Duomo cathedral.