San Francisco police arrested Mark Andrus early Saturday morning, in connection to human body parts that were found stuffed in an abandoned suitcase on a street earlier this week. Authorities detained Andrus, 59, at an apartment building Friday night as a “person of interest,” after receiving an anonymous tip, according to San Francisco Bay Area news station KNTV.

The dumped suitcase was found Wednesday afternoon in San Francisco’s South of Market (SOMA) neighborhood, one block from Twitter’s headquarters. Police then discovered more dismembered parts in a nearby trash can, the Associated Press reported.

The remains are those of an unidentified light-skinned male and the cause of death is under investigation. The California Department of Justice Bureau of Forensic Services DNA Laboratory is working to identify the remains, the San Francisco Chief Medical Examiner’s office told KNTV.

Andrus was booked for murder and he is being held without bail, the San Francisco Chronicle reported. Police have not yet released a booking photo. The case is still under investigation and police will not release pictures of the suitcase, according to KNTV.