CNN  — 

Four people have died on Poland’s border with Belarus in recent days, amid accusations that the Belarusian government is funneling migrants to the European Union’s eastern border in retaliation over western sanctions.

Three people were found dead on the Polish side of the border after suffering from hypothermia, Polish authorities said. A fourth person was found dead in Belarus, one meter from the border, Belarusian state agency Belta reported.

A growing number of migrants have been illegally crossing Poland’s border from Belarus in recent weeks. In August alone, 3,000 people – many from Afghanistan and Iraq – attempted to enter Poland illegally, according to the Polish interior ministry.

In a press conference Monday, Poland’s Minister of Internal Affairs and Administration Mariusz Kamiński said one of the victims found Sunday was an Iraqi citizen who died near the Lithuanian border in Frącki, Poland.

Kamiński said the Iraqi citizen and the two other victims found in Poland were forced to the Polish border by Belarusian border guards, before Polish border authorities told them their crossing was illegal and there was no way through.

Warsaw residents light candles at the national border guard headquarters, in a sign of mourning for the migrants found dead over the weekend.

It is not the first time Poland has accused Belarus of sending migrants to its border. In a joint statement in August, the prime ministers of Poland and Baltic countries Latvia and Lithuania, which also border Belarus, blamed President Alexander Lukashenko for systematically organizing the ongoing refugee crisis, “unlawfully” directing refugees and migrants to the EU external border in what they described as a “hybrid attack” against the entire bloc.

The leaders said that they would take in any refugees crossing the border but would call for “possible new restrictive measures by the EU to prevent any further illegal immigration.”

But Poland has received sharp criticism over its treatment of migrants. The country has begun to build a barbed wire fence to curb illegal migration and Polish President Andrzej Duda in early September declared a 30-day state of emergency in a stretch of its border with Belarus.

European officials have also accused Belarus of encouraging people to cross illegally into Poland, and its other EU neighbors, as part of efforts to put pressure on the bloc over sweeping sanctions it imposed on Minsk. The sanctions by the EU, the US and Britain in June were a coordinated response to the Lukashenko government’s forced landing of a Ryanair flight and arrest of an opposition journalist as well as “continuing repression” in the former Soviet state.

Lithuanian officials say migrants are being flown from the Middle East to Minsk, and then guided to the Belarus-Lithuania border by unspecified facilitators, where they are allowed to cross unimpeded by Belarusian border police. Lithuania has called it “petty” and “mass revenge” for the EU sanctions.

A Western intelligence official told CNN in August that the scheme could not function without the permission of the Belarusian state, and that Lukashenko was likely using the migrants as a way to pressure the EU into negotiations to lift the sanctions against him.

Lukashenko himself publicly threatened to flood the EU with “migrants and drugs” in May.

The UN Migration Agency said in a statement earlier this month that it was deeply concerned by the “dire conditions” faced by migrants at the EU-Belarus border, where a group of around 30 migrants had been stuck for several weeks with limited access to drinking water and food, medical assistance, sanitation and shelter.

In a press conference earlier this month, Kamiński described the group of migrants stuck at the border as “the tip of the iceberg,” adding “our security is at risk, and we act in proportion to the scale and degree of the threat.”

“Lukashenko wants to threaten us. We will not allow Poland to be another route of mass transfer of illegal immigrants to the EU. We will not allow the security of our citizens to be compromised. These activities are aimed at ensuring security on the Polish border, its integrity and the safety of citizens who live at the border,” Kamiński said.

CNN’s Stephanie Halasz and Nick Paton Walsh contributed to this report.