Ukraine's opposition parties are demanding the resignation of the country's police chief after two police officers were detained on charges of brutally raping a young woman.

A 29-year-old single mother was gang-raped in a small town in southern Ukraine last week. A police officer and an accomplice were arrested shortly afterwards. The victim named a second officer as the ringleader, but he was taken into custody only a week later after hundreds stormed the local police station.

Opposition lawmaker Roman Zabzalyuk told a parliament session Wednesday that Interior Minister Vitaly Zakharchenko, a staunch ally of President Viktor Yanukovych, must resign.

The case has caused widespread anger among Ukrainians, who say that the impunity of government officials has increased markedly since Yanukovych came to power three years ago.