The police on Saturday raided a plastic surgery clinic in a possible probe into allegations that Lee Boo-jin, a daughter of Samsung Group patriarch Lee Kun-hee, may have abused an addictive substance.

Investigators from the Seoul Metropolitan Police Agency seized medical records and a narcotics log book of the clinic in southern Seoul in an eight-hour raid that ended early on Sunday morning.

Last Thursday, the police had demanded the clinic voluntarily hand over their documents without seeking a warrant, but the clinic had refused to comply.

The preliminary investigation came a day after local media outlet Newstapa reported that Lee took propofol at least twice a month, according to a former nurse's assistant who worked at the clinic between January and October of 2016.

Lee, the CEO of Hotel Shilla, denied the allegations last week. Hotel Shilla said that Lee visited the clinic to receive treatments, but wasn't given propofol on a regular basis.