The European Union has announced an antitrust investigation into Google’s acquisition of Fitbit.

The European Commission, the EU’s antitrust law enforcement agency, announced today that it will launch an in-depth antitrust investigation into Google’s acquisition of Fitbit. The European Commission said today that it was concerned that the deal would further strengthen Google’s dominance of the online advertising market. The European Commission says Google already has huge amounts of data to provide personalized advertising services. The acquisition of Fitbit will further increase Google’s data volume.

The European Union has announced an antitrust investigation into Google's acquisition of Fitbit.

“This deal will further increase the amount of data Google collects through wearables, and this investigation is designed to ensure that Google’s control of that data does not distort competition,” said Margrethe Vestager, the EU’s antitrust commissioner. “

In November, wearables maker Fitbit announced that it had signed a final deal with Google to buy Fitbit for $7.35 a share in cash, valuing it at $2.1 billion.

Analysts say the deal will help Google compete with apple and Samsung in the highly competitive market for fitness trackers and smartwatches. Other competitors in the market include Huawei and Xiaomi.

Privacy and consumer groups then called on authorities to block the deal, citing privacy and antitrust concerns. In an effort to win EU approval, Google last month promised not to use Fitbit’s health data to help deliver targeted advertising services. Now, google’s commitment is not enough to reassure the EU.

  In deeds, several people familiar with the matter said on Thursday that the European Union would launch a full antitrust investigation into Google’s acquisition of Fitbit this week. The European Commission will launch an antitrust investigation into the deal after a preliminary review on August 4, according to one of the people familiar with the matter. In the four-month survey, the EU is expected to conduct an in-depth assessment of the use of data in the health care sector.