Police in South Korea have raided Google's headquarters in Seoul.
A police statement said they suspected Google has been collecting and storing data on "unspecified internet users from wi-fi networks".
The firm recently admitted that its Street View cars had been collecting information over unencrypted wi-fi networks, calling it "a mistake".
Google is currently under investigation in a number of countries to see if it broke data protection or privacy laws.
"[We] have been investigating Google Korea on suspicion of unauthorised collection and storage of data on unspecified Internet users from wi-fi networks," the Korean National Police Agency (KNPA) said in a statement.
Korean media reported that 19 KNPA agents raided the office, seizing hard drives and related documents.
Authorities said they plan to summon Google officials for investigation once analysis on the confiscated items is complete.
A spokesperson for Google told BBC News that the raid was part of the KNPA's "investigation on data collection on Street View Cars".
"We will co-operate with the investigation and answer any questions the police may have," the spokesperson added.
The raid is the latest development in what has evolved into a long running saga for Google.
The problem first came to light in May 2010, when German authorities asked to audit the data the company's Street View cars gathered as they took photos viewed on Google maps.
It emerged that the firm had wrongly collected information people sent over unencrypted wi-fi networks.
The news prompted an investigation in almost every country Street View cars had been operating, as well as an American multi-state investigation into Google's collection of wi-fi data, headed up by Connecticut's Attorney General Richard Blumenthal.
While many of the investigations are still ongoing, the UK's Information Commissioner Office cleared Google of wi-fi snooping, saying it did not grab "significant" personal details when collecting the data.
The news comes as the firm announced that it will introduce Street View for 20 of Germany's largest cities, including Berlin, Munich, Frankfurt and Hamburg, before the end of the year.