A group of Polish students and their teacher arrested in Nigeria during protests against government policies and soaring living costs have been released, Poland's foreign minister said on Wednesday.

The seven Polish citizens were detained earlier this month in the northwestern state of Kano "over their suspicious role in the protest and flying of Russian flags", according to the Nigerian national security agency.

The Polish authorities, however, said they were University of Warsaw students and a teacher, who found themselves "in the wrong place at the wrong time".

Polish Foreign Minister Radoslaw Sikorski said the group had now been released.

"I would like to confirm that the young people are already free, back in Kano, on campus, with passports," Sikorski said in a video posted on X, formerly Twitter.

"I think the young people received an accelerated lesson in African studies... I hope they will be back in the country soon," he added.

Nigeria is struggling with its worst cost-of-living crisis in years after President Bola Ahmed Tinubu introduced reforms to help revive the economy and foreign investment.