Singapore authorities arrested a man on his return to the city-state on Wednesday after he was jailed for spying for China in the US, saying they would investigate whether he posed a security risk.
Dickson Yeo, a Singapore citizen, returned to Singapore after serving prison time in the United States for acting as an illegal agent of Chinese intelligence.
The Internal Security Department (ISD) will interview Yeo to establish if he had engaged in activities prejudicial to Singapore's security, it said in a statement.
"Singapore will not allow our nationals to be subverted or used by any foreign actors for activities prejudicial to our security and national interests," the ISD said.
"The government takes a very serious view of any Singaporean who enters into a clandestine relationship with a foreign government and engages in espionage or subversive activities at the behest of the foreign power," it said, adding such individuals will be dealt in accordance with local laws.
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