SINGAPORE - Hong Kong pro-democracy activist Nathan Law was denied entry into Singapore last Saturday and flew back to San Francisco after being detained and questioned by immigration authorities, the Singapore government said.

"Law's entry into and presence in the country would not be in Singapore's national interests. A visa holder is still subject to further checks at point of entry into the country," Singapore's Ministry of Home Affairs said in a statement on Monday.

The political activist, who lives in exile in Britain, fled from Hong Kong in 2020 after the Hong Kong police issued an arrest warrant for offences under the national security law.

According to the ministry, Law arrived at Singapore's Changi Airport from San Francisco on Saturday and was placed on the earliest flight back to the U.S. city on Sunday.

In Beijing, Chinese Foreign Ministry spokesman Guo Jiakun said at a press conference that he was unaware of the situation, but added "countries have the right to make their own decisions" regarding immigration affairs.