A Chinese PhD student was found guilty Wednesday in a London court of drugging and raping 10 women in England and China, as police warned there could be more than 50 other victims. Zhenhao Zou, 28, was convicted of the attacks between 2019 and 2023 following a monthlong trial at the Inner London Crown Court. He was convicted of 11 counts of rape, with two of the offenses relating to one victim.

After more than 19 hours of deliberations, jurors concluded Zou raped three of the women in London and seven in China. Police have only been able to identify two of the victims and said after the verdict that more than 50 other women may have fallen victim to Zou, which would make him one of the worst sex offenders in U.K. history.