Sohu, a Chinese online news portal, yesterday said it's suing the developer of a popular smartphone news app for 11 million yuan ($1.8 million) in compensation for copyright infringement.

Sohu said the Today's Headlines app has been copying the content on Sohu's website and displaying the articles on the app, along with in-app advertisements.

Sohu claimed the app has been providing unauthorized links to about 630 stories on Sohu's website in the recent two months.

However, Beijing-based Byte Dance Technologies Co argued it has a long-standing collaboration deal with Sohu that authorizes Today's Headlines to use Sohu's content. The developer said the app didn't infringe Sohu's copyright and instead it has been channeling a considerable number of mobile viewers to Sohu's news app.

Sohu's suit has been accepted by Haidian District People's Court in Beijing.

Byte Dance said Today's Headlines, which claims a monthly average of 40 million active users, is willing to "collaborate with media publishers and use our technology capabilities to enable media to find new business models in the mobile Internet era."

Earlier this month, the app developer said it has raised US$100 million in its third round of financing.