Police officials told ABC News that at least 40 police officers and forensic workers took part in the search at an isolated mansion outside the village of Termal, in Yalova province.
Speaking on the condition of anonymity, a Turkish official familiar with the investigation told ABC News that investigators are searching for the remains of Khashoggi's body. They took water samples from a well on one of the properties as well as from a swimming pool, he said, and all samples will be sent to a criminal lab for forensic analysis.
On Monday morning, police and forensics teams were seen going in and out of the property, and at least one fire truck arrived at the house, according to the official Turkish state news outlet Anadolu News Agency.
The same three-story villa in Yalova was raided by roughly 40 policemen on Oct. 23 according to the Hurriyet newspaper, after it was discovered that one of the members of the Saudi hit squad who allegedly killed Khashoggi had called the owner of the villa on the day of the murder.
During the initial search in October, police said they explored the buildings on the compound, but this morning authorities returned with dogs and drones to begin a more detailed investigation of the grounds.
The owner of the villa is a Saudi Arabian businessman who left Turkey shortly after the murder and has not returned, the same official told ABC News.
Termal is a village in the Marmara region of Turkey, about 50 miles from Istanbul. It is renowned for its hot springs and rural setting, which attracts large numbers of tourists from the Gulf region every year.
Yalova Gov. Muammer Erol confirmed to the Associated Press that a search related to Khashoggi's killing was taking place but said he was not authorized to divulge any information.