German MEP Silvana Koch-Mehrin has resigned as vice-president of the European Parliament, amid claims she plagiarised her university thesis.
Heidelberg University said it has launched an investigation.
The scandal follows the resignation of former defence minister Karl-Theodor zu Guttenberg who faced similar accusations. The Guttenberg scandal prompted a group of anonymous Internet activists to examine the academic work of leading politicians.
Koch-Mehrin also stepped down from the cabinet of the liberal Free Democrats. It is yet another blow to the party, which is in turmoil after leader Guido Westerwelle was forced to step aside last month.