WARSAW - Poland on Monday accused Russia and Belarus of orchestrating a wave of illegal immigration at its land border, a day after four migrants were found dead at its Belarusian frontier.
Thousands of migrants -- mainly from the Middle East -- have been trying to cross from Belarus into EU members Latvia, Lithuania and Poland in recent weeks.
The EU suspects the influx is being orchestrated by Belarusian President Alexander Lukashenko in retaliation over sanctions on his regime.
"We're dealing with a mass organised, well-directed action from Minsk and Moscow," Polish Prime Minister Mateusz Morawiecki told reporters in Warsaw, adding that up to 7,000 migrants had been spotted on the border since early August.
"It's clear that on the Belarusian side, on the Russian side -- because probably nobody believes that this is an independent action by Lukashenko -- there is great determination and tens of thousands of people have already been brought to Belarus" from the Middle East and Africa via visa-free travel, Morawiecki said.
Those migrants are being used to apply the "pressure of illegal immigration to the EU's external border", he added.
Four people were found dead on Sunday on the Belarus-Polish border according to officials from both countries, a week after Warsaw imposed a state of emergency because of the migrant influx.
Eight exhausted migrants were also found stuck in marshy terrain elsewhere along the border, Polish border guards said. Seven of them required hospitalisation.
Earlier this month, Poland imposed a 30-day state of emergency banned non-residents including media from the border area, the first time the country has used such a measure since the fall of communism in 1989.
It has also sent thousands of soldiers to the border and started building a barbed-wire fence.
In early August, Belarus said it had discovered a dead Iraqi man near its border with Lithuania, claiming he was murdered.
Western governments have slapped several sets of sanctions on Belarusian leaders over a crackdown on dissent that began when protests erupted across the country following a disputed election last year.