According to the Finnish Border Guard, some 300 asylum seekers arrived in the country this week, the BBC reported.
On Friday alone, there were 100 such arrivals.
The closure of the Vaalimaa, Nuijamaa, Imatra and Niirala border posts in south-east Finland on Friday night came after Helsinki accused Moscow of channelling migrants to the crossings in retaliation for the Nordic nation joining the NATO.
The Finnish Border Guard said barriers would be put up at the four points after it witnessed a surge in illegal crossings by citizens of countries including Syria, Yemen and Iraq.
While confirming the closure of the four border crossings, Prime Minister Petteri Orpo informed that the points at Salla and Vartius in Finland’s far north would remain open for asylum applications.
He also accused Russia of deliberately helping people without the proper documents to get to the border.
Reacting to Finland’s decision, Kremlin spokesman Dmitry Peskov said on Friday night that” the Finnish authorities have taken the path of destroying bilateral relations”, Russian state news agency TASS reported.
“Russia has never in modern history threatened Finland, we had no reason for any confrontation. Now they have chosen this path. From our point of view, this is a big mistake,” he added.
Finland shares a 1,340 km border with Russia, Europe’s longest.