German police issued an international warrant in early February for the arrest of 29-year-old Ali Kur after matching clues from the crime scene to his apartment next door to the girl's home. Kur had been a resident of Germany since 2001 and left the country with his wife two days after the murder, police said.
The key to Kur's arrest came from his father-in-law, who had planned a meeting with the suspect, authorities said. Paderborn police are in contact with Turkish police in Ankara and await further details.
Kardelen was reported missing in the German state of North Rhine-Westphalia on January 12. Her body was found near a lake some 60 kilometres from her home. Police said she was sexually assaulted before being suffocated.