Crime Library: Criminal Minds and Methods

Marleen Konings: The Missing Dutch Girl


Detectives continued to question Mostert, and finally he admitted to having shot Marleen. According to him, however, it had been an accident.

A similar 22 caliber Llama
A similar 22 caliber Llama

This led to the discovery of a revolver—a .22 Llama—which was later positively linked to Marleen's body. It had been in a hidden section of Mostert's backpack all along. He had stolen it shortly after his release on parole.

Mostert described how he had met the blonde Dutch girl on December 24 in the Mossel Bay guesthouse they had both been staying at. Marleen came to sit with him and they began to talk. He introduced himself as Rob Cowley, a name he'd seen in an obituary. They discovered that they shared an interest in computers and ate together that night. They spent Christmas day together as well. Since he said he was also en route to Cape Town, Marleen asked him to travel with her.

The two set off in Marleen's rented car on the 26th. Both became ill, though, and they visited a doctor in Riversdale, where they received treatment for food poisoning. They spent the night at Lulu's Place in Swellendam. Marleen struggled to sleep and was nauseous and sick throughout the night, Mostert said, so he put Sepenax tablets in her bottle of mineral water. The following day, while driving around, they both drank from the same bottle, and both became ill again. (Whether this was related to the pills or something else is unclear.) This time they went to a doctor in Barrydale, but went back to Lulu's Place towards the evening.

Although they had shared a room on a number of occasions, Mostert remained adamant there had been no physical relationship between them.

They left Swellendam for the last time on December 29, Mostert said, "and what happened further on that day you know about," according to Independent On-Line on December 2, 2004. It would seem that this was the day, then, on which Marleen Konings had died.

Mostert agreed to repeat his confession at the magistrate's office, which he did on Monday, January 19, before Magistrate Erna Grobler. According to Mostert, on December 29, he and Marleen had stopped in the small town of Barrydale to have some beer. They stopped again at the Tradouw Pass, because the student wanted to take some pictures with her digital camera.

"A little buck came out of the bush and ran across the road," Mostert said, as quoted in the Cape Argus of December 2, 2004. "I took the firearm out and wanted to shoot the deer by the water. There was a river below. I followed it. She was standing taking pictures. As I wanted to shoot the deer, she started to scream. She turned her back on me and closed her eyes. I told her to stop screaming, but she did not. I fired a shot at her. She fell down and I just ran away up the hill. I got in the car and drove away."

This shot that Mostert just "fired" at the screaming girl hit her in the back of her head, killing her. But it was all just a terrible accident.

Capt. Viljoen was not convinced. The evidence did not support Mostert's story. The foliage and surroundings where Marleen's body had lain made it impossible to stand there.

Mostert told the detective, according to Die Burger of December 3, 2004, that "the revolver was cocked. I don't know why. And the trigger was very light."

As he drove away, Mostert dumped some of Marleen's clothes and luggage, while he sold the valuable items at various used goods stores. He also used her credit card on a number of occasions, while impersonating its owner, in particular to pay for lodging. When he ran out of money, he ditched the hired car near Colesberg.


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