He was blamed for Gulabohs death.
Anu went to see Gulaboh, to persuade her one last time to help. They were on the terrace.. She agreed and everything was going fine until Ritesh showed up behind Anu.. scaring Gulaboh which led her to walk backwards and without realising she fell off the building.
Anu was blamed by witnesses etc for her death - calling it a murder. Hence why hes been arrested.
Hope that helps 😊