FINNISH border guards and soldiers began erecting barriers including concrete obstacles topped with barbed wire at some crossing points on the Nordic country’s lengthy border with Russia to better control an influx of migrants, officials said on Wednesday. 

Finland said that it will close three more crossing points along the 830-mile border, leaving only one Arctic point open for refugees seeking asylum.

Some 600 migrants without valid visas and documentation, mostly from the Middle East and Africa, have arrived in Finland in November compared to a few dozen in September and October. 

The arrivals include residents of Afghanistan, Iraq, Syria, Yemen, Kenya, Morocco and Somalia, border officials said.

Tomi Tirkkonen, deputy commander of the Kainuu border guard district in eastern Finland, said: “We need to do this to maintain order (at the crossing points) and guarantee the security of legal border traffic.”

Russian Foreign Ministry spokeswoman Maria Zakharova said on Wednesday that Russian authorities are ready to work together with Finnish officials to reach an agreement on the border issue. 

She argued that Finland should have “put forward its concerns” before acting unilaterally.

Finland, a nation of 5.6 million people, joined Nato in response to Russia’s war with Ukraine.