The explosion is said to have taken place in the Polish city of Przewodów, just a couple of kilometers from the Ukrainian border.
Two people are said to have died in connection with the explosion.
The explosion must have occurred at 3:40 p.m., according to TT, which referred to Polish media.
At about the same time, Russian robot attacks against Ukraine were underway.
Among other things, towards Lviv, which is ten kilometers south of the Polish city of Przewodów.
- Firefighters are on the scene, it is unclear what has happened, says Lukasz Kucy, who works as a fire brigade nearby, reports Reuters.
Polish Prime Minister Mateusz Morawiecki called a crisis meeting on Tuesday.
Later in the evening, the Polish government confirmed that two people had been killed in an explosion.
Government spokesman Piotr Mueller also announced that the country is raising its military readiness and that they are investigating whether they need to activate NATO's Article 4.
The Pentagon has not yet confirmed the information.
- We are aware of the media reports which claim that two Russian robots struck a location in Poland near the Ukrainian border.
We have no information to confirm these reports and we are investigating this further, Pentagon spokesman Patrick Ryder said at a press briefing.
Russia denies the information
Russia dismisses reports of a Russian attack on Poland, reports the Reuters news agency.
The Russian Ministry of Defense instead describes the attacks as a "deliberate provocation intended to escalate the situation".
In a statement, the ministry writes:
"No attacks on the Polish-Ukrainian border have been made with Russian weapons."