D. Tusk announced that one of the suspects is a Ukrainian citizen, convicted by a Lviv court in May of this year for acts of sabotage on Ukrainian territory, and living in Belarus.

The second suspect is from Donbass. Both lived in Belarus and entered Poland through the Terespol border crossing this fall.

"In both cases, we are certain that the attempt to blow up the tracks and damage the railway infrastructure was deliberate and had its perpetrators. Their goal was to cause a tragedy," he said.

He stressed that their identities have been established, but he cannot make them public as this could hinder the investigation.

The Polish Prime Minister announced that a total of 55 people have been detained in Poland for acts of sabotage.

"Today in Poland we are faced with an act of sabotage that could have caused a serious catastrophe with casualties. That is why I say that the line has been crossed, and this is a very, very serious matter," said Tusk.

"The head of the Internal Security Agency and the Minister of the Interior and Administration have asked me to introduce the third level of alert - "Charlie" - due to terrorist threats. This level will apply to specific railway lines. In the rest of the country, the second level of alert will remain, as before. I will issue a corresponding order today," the Polish Prime Minister informed.

"We are facing an unprecedented event. This is perhaps the most serious situation of this kind from a national security perspective since the start of the large-scale war in Ukraine," he stressed.

Important hint

Polish special services have identified the person in whose name the SIM cards used to remotely detonate explosives on railway tracks were registered, reports the Polish portal RMF24.

According to the portal's journalists, the explosives were detonated remotely using a phone.

One of the explosive devices detonated, while the other failed to explode for unknown reasons. Law enforcement officers removed the SIM cards from them and determined the passport details they were registered with.

Media outlets have noted that these are cards from a Polish mobile operator. Investigators emphasize that the owner of the passport is not necessarily a criminal, but this evidence is considered"very important."

The Polish prosecutor's office is investigating these incidents as acts of terrorism, probably carried out on the orders of foreign intelligence, RMF24 adds.

Poland: Everything indicates that Russia is behind this

Jacek Dobrzynski, a spokesman for the minister coordinating the work of Poland's special services, recently confirmed that"everything indicates" that Russian intelligence services are responsible for the acts of railway sabotage in Poland over the weekend.

"Everything indicates that this... we can now boldly call it a terrorist attack, was initiated by Eastern special services," he later added.

However, he stressed that it is necessary to ensure the confidentiality of the investigation into both incidents at this time in order for the investigation to be effective.

"I cannot say what specific actions the officers are currently taking or what stage of the investigation they are at, what possible links they are analyzing. The Russian services would very much like to receive this information: where our officers are and in what direction they are working," he said.

He stated that a lot of evidence had been collected

Polish law enforcement agencies have collected evidence that will help investigators very quickly identify the suspected perpetrators of an act of sabotage on the country's railway line over the weekend, cabinet representatives said on Monday evening, quoted by TVP World.

Polish government ministers held a joint press conference on Monday to discuss the incidents on a railway line in the country's southeast. Interior Minister Marcin Kierwinski confirmed that an explosive device was"without a doubt" used in the attack.

At a press conference also attended by Justice Minister Waldemar Żurek, Infrastructure Minister Dariusz Klimczak and Special Services Coordinator Tomasz Siemoniak, the Interior Minister said that video footage from surveillance cameras in the area had been collected.

Mr. Kierwinski added that"a wealth of evidence," including surveillance camera footage and other material,"will certainly help to identify the perpetrators of this terrible sabotage very quickly."

Special services coordinator T. Siemoniaks said that the incidents were most likely ordered by foreign actors.

"We will ensure that the criminals and those who ordered this attack are brought to justice in Poland," he added.

Justice Minister W. Żurek stated that those suspected of sabotage could be sentenced to 10 years to life in prison.