Head of the police cyber crime unit, Chang Byuk-Duk, told the Agence-France Presse that the police were sent to the company's offices to secure evidence related to the AdMob platform. Google is accused of gathering data on users' locations via smartphone applications. The local site Daum was also raided, based on similar allegations.
Chang told the press that the police couldn't get certain information because the server is located in the U.S. He added that Google officials promised to cooperate at a later date.
The raids come a week after the South Korean telecommunications regulator started an inquiry into the use of location data by Apple. Such data collection might violate South Korean privacy laws.
Apple and Google are both under scrutiny in the U.S. because the iOS and Android operating systems create databases of local cell towers and Wi-Fi hotspots, which can in turn be used to pinpoint a user's location over time.
Both companies have said they aren't tracking individual users. Apple says the data is anonymized and can't be traced to a single person. Google, for its part, notes that the location data file holds only 50 cell towers or 200 Wi-Fi locations, limiting the amount of time it covers.
Apple has promised to fix one part of the data-gathering that allowed an unencrypted file of the locations to be stored for up to a year. The company says the location data is part of a plan to crowdsource locations so that certain apps run more efficiently and new services can be tailored that are based on where a user is.