HONG KONG -- Two former editors from a Hong Kong online pro-democracy news outlet were charged with sedition and denied bail Thursday, a day after one of the last openly critical voices in the city said it would cease operations following a police raid on its office and seven arrests.

Hong Kong leader Carrie Lam defended the raid on Stand News amid a wider crackdown on dissent in the semi-autonomous city, telling reporters that "inciting other people ... could not be condoned under the guise of news reporting."

U.S. Secretary of State Anthony Blinken called on Hong Kong authorities to release the detainees, and Canadian Minister of Foreign Affairs Melanie Joly said her country was deeply concerned about the arrests, which included singer Denise Ho, a Canadian citizen and activist.

According to a charge sheet, national security police filed one count each of conspiracy to publish a seditious publication against Chung Pui-kuen and Patrick Lam, former editors at Stand News. Police also said they would prosecute the company for sedition.

The cases were brought to West Kowloon court on Thursday, police said in a statement. Lam was not present in court because he was in the hospital. Both were denied bail.

The others have been detained for further questioning. They include four former Stand News board members, including Ho and former lawmaker Margaret Ng. Ho was released from police custody on Thursday afternoon.

Chan Pui-man, a former editor at the pro-democracy Apple Daily newspaper and Chung's wife, was also arrested. Apply Daily was forced to cease operations earlier this year after its publisher, Jimmy Lai, and top editors were arrested and its assets frozen.

The seven were arrested on Wednesday under a crime ordinance that dates from Hong Kong's days as a British colony before 1997, when it was returned to China with a promise from Beijing that it would keep Western-style freedoms for 50 years. If convicted, they could face up to two years in prison and a fine of up to 5,000 Hong Kong dollars (US$640).

"Journalism is not sedition, but seditious acts and activities and inciting other people through other acts and activities could not be condoned under the guise of news reporting," Lam, the Hong Kong leader, told a news conference. "It should be very clear what is reporting of news, and what is seditious acts or activities to undermine national security."

Blinken criticized the arrests, saying that by silencing independent media, Chinese and local authorities undermine Hong Kong's "credibility and viability. A confident government that is unafraid of the truth embraces a free press."

"Freedom of expression, including media freedom, and access to information provided by an independent media are critical to prosperous and secure societies. These freedoms enabled Hong Kong to flourish as a global centre for finance, trade, education, and culture," he said.

Joy tweeted that "freedom of media and expression remain cornerstones of democracy and essential to the protection of human rights and fundamental freedoms." She said that Canada will continue to speak out and denounce violations of these freedoms, in partnership with our international allies.

Stand News said Wednesday that it is ceasing operations and had laid off all its staff.

The United States has also sanctioned five Hong Kong-based Chinese officials following legislative council elections in the city earlier this month for reducing Hong Kong's autonomy and freedoms.

Chinese Foreign Ministry spokesperson Zhao Lijian said at a daily briefing Thursday that China will respond by imposing countermeasures on five Americans, including former Commerce Secretary Wilbur Ross and U.S.-China Economic and Security Review Commission President Carolyn Bartholomew.