Italian police moved to disperse around 200 migrants who were staging a sit-in at a border crossing with France after French police refused to let them enter the country.
Officers in riot gear pushed the migrants back towards the town of Ventimiglia yesterday, five kilometres from the border.
However, a group of around 50 men slipped away from the police cordon and took refuge on rocks near the border post.
"Where are our human rights?" some of the men shouted, claiming they had been treated roughly by the police.
An Italian official said the protesters would be taken by bus to reception centres in the western province of Imperia.
Some of the migrants refused entry into France had gone on hunger strike and others organised a sit-in at the border crossing and tried to block traffic.
They included men, women and children, with many coming from Somalia, Eritrea, the Ivory Coast and Sudan. They reached Italy by taking the often precarious boat crossing from Libya.
Many hoped to travel onwards to Germany, Britain or Sweden to request asylum, but French border police told AFP earlier they had been ordered not to let the migrants through.
"We are not going back, we need to pass," read a large banner held aloft by one group of migrants, while another read: "We need freedom."
Before the Italian police made their move, the migrants curled up on pieces of cardboard and sheltered under trees and bushes.
While the women and children ate food provided by the Red Cross, the men refused.
"We won't eat," said 20-year-old Mustapha Ali. "We spent all of yesterday in the heat, and last night in the rain and cold. If we must die here, there is no need to eat."
A record number of 1,439 migrants were intercepted this week by French police in the Alpes-Maritimes region of southeast France, with 1,097 returned to Italy.
Mohamed from Sudan told AFP he had arrived in Sicily with his brother and travelled by car and train as far as Menton in France -- just across the border -- where he had been arrested at the train station and escorted back to Italy.
The Schengen open borders accord means migrants landing in Italy can usually easily travel through neighbouring France, Austria, Switzerland and Slovenia as they seek to make it to Britain, Germany and Scandinavia.
But border controls have been temporarily reintroduced due to a recent summit of G7 leaders in Germany.
A source close to French Interior Minister Bernard Cazeneuve told AFP yesterday that the police action was designed to catch people smugglers and to stop more migrant camps being set up in France.
"We cannot allow illegal migrants into France with Europe facing this exceptional wave of migration," the source added.
