"The Polish government can't agree to discrimination against our citizens," Polish Deputy Foreign Minister Paweł Jabłoński wrote on the X social media platform on Friday.
"Those responsible for this must face consequences," he added. "We count on cooperation with the competent authorities of the Kingdom of the Netherlands in this matter."
The Dutch ambassador is expected to visit the Polish foreign ministry on Saturday, public broadcaster Polish Radio’s IAR news agency reported.
The announcement came after Legia Warsaw president Dariusz Mioduski received heavy-handed treatment from Dutch police and two players were detained following a Europa Conference League match between the Polish soccer club and the Netherlands' AZ Alkmaar, according to officials.
The two players, Josué of Portugal and Radovan Pankov of Serbia, were taken off the team bus after the game and detained for almost 24 hours after being accused of injuring a steward, according to news reports.
Speaking at a news conference in Warsaw on Friday, Mioduski said: "What happened is an absolute scandal. For many years I have gone to matches from Kazakhstan to Portugal and I have seen a few situations, for example, when our team bus was attacked by rival fans, but I have never seen the team, staff members and management attacked by security and the police. It's unprecedented on a global scale."
Thursday's game in Alkmaar saw trouble between visiting supporters and police, the AP news agency reported.
It said the Dutch side was blaming Legia and their fans for having started a chain of aggression that led to scuffles with police after Legia lost 0-1 to Alkmaar in their European game.
Polish Prime Minister Mateusz Morawiecki said on Friday he had asked his country's diplomats to investigate the matter.
"Polish players and fans must be treated according to law," Morawiecki said on X, previously Twitter. "We do not agree to law violations," he added.
The secretary general of the Polish Football Association (PZPN), Łukasz Wachowski, said he was demanding explanations from his Dutch counterparts and the European soccer body UEFA, news agencies reported.
UEFA said it was gathering evidence to consider possible disciplinary cases, according to the AP.
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Source: IAR, PAP, Reuters, AP, BBC