30-year-old American Edward Snowden, a contract employee at the National Security Agency, is the whistleblower behind significant revelations that surfaced in June 2013 about the US government's top secret, extensive domestic surveillance programmes. Snowden flew to Hong Kong from Hawaii in May 2013, and supplied confidential US government documents to media outlets including the Guardian.
Snowden drama triggers calls for Hong Kong to tighten surveillance law
Ordinance controls government bodies but not snooping by ordinary members of the public
Hongkongers worried about privacy online have laws to protect them from unauthorised snooping by the city's government - but not from covert surveillance by fellow members of the public.
Fallout from US cyberspying whistle-blower Edward Snowden's flight to Hong Kong has prompted lawmakers to renew calls for tighter surveillance laws.
Under the Interception of Communications and Surveillance Ordinance, introduced in 2006, four law enforcement agencies are restricted in their spying activities.
The four - the Customs and Excise Department, the police, the Immigration Department and the Independent Commission Against Corruption - must seek approval from a panel of judges before they intercept communications. But a breach of the ordinance is not a crime and would be dealt with through internal disciplinary procedures.
In 2010, the then commissioner on interception of communications and surveillance, Mr Justice Woo Kwok-hing, called for greater access to details of wiretaps to protect the public.
"It's a grave concern because there are no checks and balances and no deterrent for police who tap phones of people they should not be tapping," said Civic Party lawmaker Ronny Tong Ka-wah.
Democratic Party lawmaker James To Kun-sun said the government must make it a crime for authorities to breach the rules.
In 2011, 137 people were arrested as a result of authorised wiretaps and covert surveillance, according to government figures.
One concern is that there is no specific law to prevent members of the public from carrying out covert surveillance - although doing so may breach other laws, such as trespassing.
Politicians and activists fear they may fall victim to snooping.
"The government is unwilling to introduce a law that prohibits the common person from spying, and political surveillance may be the reason," Tong said.
"The Basic Law is clear in that it says it should restrict anyone from carrying out surveillance on anyone else," Tong said, referring to the city's mini-constitution.
"We've been arguing for years that the law should cover the entire community but the government doesn't want to. It's ludicrous and it's a great irony."
He said political figures were the most likely targets. "I suspect my phone is tapped and my e-mail is hacked but I just don't use it to send confidential information," Tong said.
A Security Bureau spokeswoman said it was in discussions with the new commissioner, Mr Justice Darryl Saw, on amending the law to allow him and his staff to "listen to and examine products" of interceptions and covert surveillance operations and would update lawmakers when its legislative proposal was ready.
But Tong believes Hong Kong's laws are strong enough to stop the wide-scale spying on the public exposed by Snowden.