"He was detained by the Border Guard Service operatives at the instruction of the Migration Service," the source told the agency.
Saakashvili's lawyer Ruslan Chornolutskyi told Interfax-Ukraine that the leader of Rukh Novykh Syl party "has already been taken away." He provided no additional information.
Earlier, Saakashvili's associate David Sakvarelidze said that the politician was detained by people in military uniforms in a Kyiv-based restaurant.
On Dec. 5, the law enforcers detained Saakashvili on charges of assisting crime ring members. His supporters blocked off the paddy wagon with the detained politician inside and later released him. During the search in Saakashvili's apartment, he went up to the roof of the house and was apprehended by the law enforcers there.
Prosecutor General of Ukraine Yurii Lutsenko later said that runaway oligarch Serhii Kurchenko funded Saakashvili's activities in Ukraine.
Early Dec. 6, a clash between law enforcers and supporters of the former Odesa region governor took place outside the Ukrainian parliament early Dec. 5 when police tried to storm the tent camp in order to locate and detain Saakashvili.
The police apprehended Saakashvili in Kyiv’s Solomianskyi district late Dec. 8. He was charged under part 2 of article 256 of the Criminal Code of Ukraine (providing assistance to crime ring members and concealment of their criminal activity) punishable by 5 to 10 years in prison.
Being placed in Kyiv-based detention center, the politician went on an indefinite hunger strike.
Saakashvili walked free from the courtroom late Dec. 11 as the court imposed no pre-trial restriction on him. The PGO later appealed against this ruling.
The politician was placed under night-time house arrest on Jan. 26, 2018.