China has announced that it has initiated an antitrust investigation into Google, as part of a swift response to the U.S. President Donald Trump’s imposition of a 10% tariff on Chinese goods.

The probe, conducted by China’s State Administration for Market Regulation, will examine alleged monopolistic practices by the U.S. tech giant, which has had its search and internet services blocked in China since 2010 but maintains operations there primarily focused on advertising.

“Because Google is suspected of violating the Anti-Monopoly Law of the People’s Republic of China, the State Administration for Market Regulation has launched an investigation into Google in accordance with the law,” the English translated version of administration’s statement read.

In addition to the antitrust investigation, Beijing has also taken further retaliatory measures against the U.S. by imposing a 15% levy on coal and liquefied natural gas exports, and a 10% tariff on oil and agricultural equipment. Chinese authorities have also added Calvin Klein owner PVH Corp. and gene sequencing company Illumina to a restricted entities list, while implementing new export controls on tungsten-related materials.

Trump’s tariffs, which he justified as a response to Beijing’s failure to prevent the flow of illegal drugs, have reignited trade tensions between the world’s largest economies just as relations appeared to be stabilizing.

This is a developing story. More to follow.