French police have blocked 200 undocumented immigrants, mostly from the African country of Eritrea, from entering French territory at the main border with Italy.

The police set up a blockade at the border crossing of Ventimiglia late last week after learning that a good number of illegal immigrants would be attempting to move north into France from the Liguria region of the Italian northwest. About 100 immigrants arrived between Friday and Saturday, but now the number is reported to have doubled.

Some of the immigrants are reportedly attempting to go to France, others to Switzerland, Germany and the UK.

According to a source within the French police, in the last week, more than a thousand clandestine migrants have been returned to Italy, of the 1,439 migrants intercepted this week by French police in the Alpes-Maritimes region of southeast France.

“We fully understand their predicament,” he said, “but this is not the place to resolve their problems.”

Liguria’s president, Giovanni Toti, called the move “an emblematic case of the inhospitality of France and other European countries.”

The French prefect of the region, Adolphe Colrat, said he was only enforcing EU regulations, but the protesters are not backing down.

“We risked our lives crossing the Mediterranean. It was hard,” said one of the migrants. “This is nothing but we do need aid and there’s nothing, no humanity. We’re ready to cross the sea again. We’re ready to die.”

In an interesting coincidence, the standoff is taking place on the thirtieth anniversary of the Schengen Treaty, originally signed on June 14, 1985, which opened borders separating European member countries in exchange for a single, external border of the entire region.

The Schengen open borders accord means migrants landing in Italy can usually easily travel through neighboring European countries, but a recent summit of G7 leaders in Germany temporarily reintroduced border controls.

About 50 immigrants are now camped out in protest on the rocks at Ponte San Ludovico in Ventimiglia, under the watchful eyes of two units of the Mobile Battalion of the Italian police. The immigrants have shouted slogans at the force, such as, “We will not go back” and “Away with the police.”

Another 100 immigrants are temporarily holed up in the Ventimiglia train station, and some have begun a hunger strike.

The mayor of Ventimiglia, Enrico Loculano, has called the situation “an emergency” that is fast becoming “a diplomatic incident.”

European Commission President Jean-Claude Juncker has sent a message that “governments should share equitably in receiving persons seeking international protection,” but exactly what this means in practice is as yet undetermined.

Juncker has defended the proposal of a mandatory distribution of refugees among the member countries and stated that “migrants seeking international protection cannot be left solely in the care of Italy, Greece, Spain and Malta.”

There will be a summit of European interior ministers on Tuesday to discuss possible alternative plans.

According to Italian Prime Minister Matteo Renzi, over 57,000 migrants and asylum seekers have been rescued at sea and brought to Italy so far this year.

The France-Italy situation underscores the extreme tension in Europe over what to do with the enormous number of migrants arriving weekly, mostly from Africa.

Follow Thomas D. Williams on Twitter @tdwilliamsrome.