It appears that the SFPD is closing the case file on last year's "suitcase murder," almost exactly a year after it occurred, despite the fact that a couple of key aspects of the case remain a mystery. The sole suspect, Mark Andrus, who died just days after being initially detained and questioned by police, never confessed to the crime, but the SFPD now believes they have enough circumstantial evidence to close the book on the case, as CBS 5 reports, which left Andrus' longtime friend, 58-year-old Omar Shahwan, dead and dismembered.

The body was discovered January 28, most of it dismembered and mutilated in a rolling suitcase that was left near the Goodwill on 11th Street. From surveillance and a tip called in to police, the suspect seen depositing the suitcase at that location was soon identified as the 54-year-old Andrus, who was staying with a friend in a public housing complex at 430 Turk Street.

Andrus was detained and questioned but not arrested, because at the time the medical examiner could not identify the remains quickly enough, or even say for certain that it was a homicide — one possibility that was floated at the time was that Shahwan died of natural or drug-related causes and Andrus mutilated and tried to hide the remains in order to collect his friend's government assistance checks.

But now, as KTVU reports via a final report from SFPD homicide detectives, police can say with certainty that Andrus killed his friend, and they know where it likely happened, despite there being no evidence of the crime to be found by the time investigators determined the location of the murder scene.

Accounts from friends led investigators to understand that Andrus was a small-time dealer of cocaine and heroin — and his ultimate cause of death was septic shock, though doctors said it was related to a lifetime of heavy drug use. Using the digital map provided by Andrus's cell phone records, police determined that Andrus and Shahwan were staying together at the Aldrich Hotel at 439 Jones Street, where they checked into Room 320 a few days before the murder.

While the exact cause of death will still never be known, investigators spoke to the person staying in the room directly next door on what was likely the night of the murder, and that person reported hearing banging on the wall, and Shahwan "begging for mercy."

Andrus then proceeded to make numerous Google searches and go shopping on Craigslist for hand saws and power tools, even searching for saws specifically "to cut up meat." Homicide investigator Sgt. Gary Watts then believes Andrus cut up the body in the bathtub of the room at the Aldrich Hotel, and managed to contain and clean up any blood. By the time he examined the room, a month after the crime would have been committed, he couldn't find any evidence of it.

Shahwan's head and hands have still never been found.

No murder weapon was ever found either, and we'll likely never know the motive for the crime, as what transpired was between two friends who had lived together, and obviously did drugs together, on and off for at least the last five years.

“Only Mark Andrus knows those answers,” said Sgt. Watts to KTVU.

All previous coverage of the 'suitcase murder' on SFist.