Poland's opposition lawmakers are demanding explanations from the ruling party about reports that its regional chapter used donations for the Red Cross to finance its parliamentary campaign.

Gazeta Wyborcza daily reported recently that Red Cross employees in southwestern Poland were selling donated clothes through second-hand shops and using the proceeds to fund the 2015 campaign of the Law and Justice party's regional candidates. The party's politicians were in charge of the charity then.

Prosecutors say Education Minister Anna Zalewska is to be questioned about allegations that her campaign was financed that way.

Opposition Civic Platform lawmakers on Thursday demanded explanations from Justice Minister Zbigniew Ziobro.

It is the latest in a series of image problems for the ruling party ahead of elections to the European and national parliaments this year.