NEW : Roommate says horrible tragedy is `` incomprehensible '' Grad student Annie Le remains found 24 in basement wall in building . Le , Sunday , was last seen entering the building 24 evening . Police : No suspects in custody , but investigators questioning several people .
NEW : Roommate says horrible tragedy is `` incomprehensible '' Grad student Annie Le 's remains found Sunday in basement wall in building . Le , 24 , was last seen entering the building Tuesday morning . Police : No suspects in custody , but investigators questioning several people .