BRUSSELS, Belgium —The European Union plans to launch more antitrust investigations into e-commerce companies after a two-year inquiry uncovered practices that restrict competition, the European Commission said on Wednesday.

In its report following the initial inquiry, the European Commission said there was an increased use of contractual restrictions to control product distribution, which could be in breach of EU antitrust rules.

"Certain practices by companies in e-commerce markets may restrict competition by unduly limiting how products are distributed throughout the EU," competition commissioner Margrethe Vestager said in a statement.

The e-commerce sector inquiry is part of the European Commission's campaign to overhaul the bloc's digital market in a bid to boost growth and catch up with the United States and Asia.

"The insight gained from the sector inquiry will enable the Commission to target EU antitrust enforcement in European e-commerce markets, which will include opening further antitrust investigations," the Commission said.

The EU executive also found that manufacturers increasingly use selective distribution systems where products can only be sold by pre-authorised sellers, giving them more control over distribution and price.

The report showed that almost 60 percent of digital content providers have agreed with the copyright holders for music, films and TV shows, for example, to geo-block, namely restricting consumers' access to products and services based on where they are located.

Some licensing practices may also make it more difficult for new online business models and services to emerge, the Commission said.

EU antitrust scrutiny of the pharmaceutical, energy and financial services industries over the past decade prompted investigations into companies in all three sectors.

By Julia Fioretti and Robert-Jan Bartunek; editor: David Clarke.