BRUSSELS: The Chinese mission to the EU on Monday said the bloc was openly interfering by criticising the arrest of a Hong Kong media tycoon, Jimmy Lai, under the territory's new security law.

"The EU side openly interferes in Hong Kong affairs and China's internal affairs by making irresponsible remarks about the law-based exercise of duties by law enforcement agencies of the Hong Kong Special Administrative Region," the mission in Brussels said in a statement on its website.

In a tweet, the mission added: "The EU side should respect facts, reject double standards, and refrain from covering up or supporting criminal suspects."

The accusations follow a statement from the EU's top foreign policy official, Josep Borrell, that said Beijing was using the security law to crack down on media freedom, meant to be protected under Hong Kong's Basic Law.

Lai, 71, was among nine detained Monday on charges that include "colluding with foreign forces" in an operation targeting his Hong Kong publishing group, Next Digital.

It was the latest police operation against dissidents under the sweeping new law introduced at the end of June, despite local street protests and international concern

Beijing has labelled Lai an "anti-China rabble-rouser".