MILAN (Reuters) - Italian police said on Monday they had smashed a criminal gang that smuggled migrants packed into vans across the border with France for up to 1,000 euros ($1,063) each.

Police issued more than 30 arrest warrants for human trafficking after a two-year investigation that documented dozens of smuggling incidents. About half the suspects targeted by the warrants lived outside Italy, the statement said.

Citing one bust, Milan prosecutor Ilda Boccassini said police had found 40 migrants crammed in the back of a van that had been padlocked shut.

“They were having difficulty breathing when the police got them out,” Boccassini told reporters, adding that the smugglers treated the migrants like “cannon fodder”.

A record 181,000 migrants reached Italy by boat last year, mostly from Libya. Many, however, try to move quickly onto other European countries where they may have family and friends, or believe they have better work prospects.

France has largely closed its border to migrants, making it tough for them to cross from Italy by road, train or on foot.

After one high-speed chase, police stopped an Italian man in October with 17 migrants in his refrigerated mini-van.

Milan was the hub for the smugglers, who hailed from Egypt, Afghanistan, Sudan, Albania, Romania, North Africa and Italy. Most of the 18 suspects wanted in Italy lived in the country legally, police said.

Most of the migrants, including children, tried to cross from the Italian border town of Ventimiglia to Nice. The Italian town was dubbed by some locals a “mini-Calais”, a reference to the now-dismantled migrant camp in northern France from where thousands of asylum seekers and economic migrants tried to reach Britain.

“The logistics base was Milan, and in particular the central train station, but a walk around the city is enough for anyone to see that there are small children awaiting the next opportunity to leave,” Boccassini said.

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