Thiruvananthapuram: Hours after registering the arrest of Greeshma, the main accused in the murder of Parassala youth Sharon Raj, police on Monday named her mother Sindhu and uncle Nirmal Kumar as co-accused for destroying evidence.

They are now in police custody, sources said.

Earlier in the day, police arrested Greeshma from the Thiruvananthapuram Medical College Hospital where she is admitted after a failed suicide bid at the police station.

Sharon's parents had alleged that Greeshma's family was involved in the murder.

Greeshma and Sharon came close during a college trip. But Greeshma distanced herself from Sharon when a marriage alliance cropped up.

Though she argued that their families would never agree to their relationship as they belonged to different castes, Sharon refused to break off their affair.

The photos and videos recorded during their relationship were on Sharon's phone. Greeshma feared that Sharon would hand them over to her fiance, the police said.

Greeshma began resenting Sharon after he refused to delete the images and videos; thereafter, she hatched the plan to poison him, the investigators said.

Police suspect she might have taken the pesticide her uncle had arranged to poison Sharon.

Greeshma occasionally stayed at her uncle's home, which is near Sharon's residence.

Greeshma, a 22-year-old post-graduate Literature student, killed Sharon, a Radiology student by spiking his drink with pesticide.