Uday Swarup, a B.Sc student at Dayalbagh Educational Institute and the grandson of a former director of the institution, was arrested on the basis of prima facie evidence along with lab technician Yashvir Sandhu for the murder of the 23-year-old Neha Sharma, who was found dead in a laboratory on March 16.
Police alleged that Swarup had confessed to the crime during his interrogation but added that they had made little headway in the case as the deceased's pen drive and mobile phone battery were yet to be recovered.
Police said that the two accused have kept misleading them regarding the location of the two items.
They led police teams looking for the above articles to several places but the search proved futile, police added.
Police said that although Swarup had told them the two items were with him, he did not help them to recover the same.
He was even taken to his residence but there, too, nothing was found.