Hong Kong's legislature has passed a controversial new law on the use of covert surveillance and phone tapping, which critics fear will harm liberties.
The bill includes provisions to tap telephones
Secretary for Security Ambrose Lee said the bill was crucial for public safety.
He also promised there would be a "good balance" between effective law enforcement and protection of privacy.
Under the law, surveillance operations have to be approved by judges appointed by Hong Kong's leader. Critics regard the checks as inadequate.
They have expressed worries that the new Interception of Communications and Surveillance law will empower police officers to eavesdrop on political opponents.
Some media groups feared conversations between reporters and sources or between lawyers and clients would also be intercepted.
The bill was approved by 32-0 on Sunday after pro-democracy legislators walked out of the marathon debate, which began on Wednesday.
One, James To, said: "This was like debating with a wall."
The government wanted to pass the legislation before Tuesday, when a court ruling that existing arrangements are unconstitutional comes into effect.