Some of these groups include legitimate political parties, others are dissidents given U.S. assistance. But they are worried that data collected by the National Security Agency (NSA) and the FBI from U.S. Web giants like Google Inc, Facebook Inc and Yahoo inc could some day be used against them.
"We share a lot of sensitive data, election-related data, using Google Docs," said Ong Kian Ming, a member of parliament for Malaysia's opposition Democratic Action Party.
"That's definitely something we are concerned about because we don't know what kind of messages are being tracked and who these messages would be given to."
Under Prime Minister Najib Razak, who won a second term last month, Malaysia has strengthened economic and security ties with the United States that had occasionally been strained in the past.
A Malaysian government spokesman could not immediately be reached for comment but Najib has said in the past that he is committed to internet freedom.
In a factsheet issued in Washington last week, the U.S. government said it can only target someone for Internet surveillance if "there is an appropriate, and documented foreign intelligence purpose" for collection.
Those purposes include countering terrorism, weapons proliferation and cyber threats, Director of National Intelligence James Clapper said in a statement after Edward Snowden, a contractor working for the National Security Agency, revealed the government's top-secret Internet surveillance programme.
There was no word whether U.S. agencies were sharing such gathered information with allied governments but British and U.S. newspapers have suggested that the NSA has handed over information on Britons gathered under PRISM, the name of the eavesdropping programme.
In Singapore, where authorities keep a close eye on opposition groups and political commentary, some people use encryption programs to avoid surveillance.
"If you are concerned about electronic eavesdropping, you can use pidgin IM - it has an encryption module for instant messaging," said Donaldson Tan, editor of socio-political website New Asia Republic.
"There is also Tor client for online anonymity," he said, referring to two popular free software programs developed by volunteer programmers to guard against network surveillance.
Asked if he was concerned whether the U.S. government would share surveillance information with Singapore authorities, given the friendly ties between the two countries, Tan said: "The U.S. is really hard to read".
A Singapore government spokesman did not immediately respond to requests for comment.
No moral high ground
Several people in the region said the reports of government access to e-mails and phone calls were not surprising.
"This latest revelation, if true, is really no more than putting proof to suspicion," said Howard Lee, a blogger who often writes about political and social issues in Singapore.
"As citizens of democracies, our response should not be fear, but a concerted voice to demand accountability and transparency. I believe this is the current aim of civil society groups in Singapore."
One nation where dissidents are relatively unconcerned about the snooping revelations is China, where government critics view Washington as an ally and domestic Internet servers as subservient to Beijing.
"I've never considered abandoning Twitter, YouTube, Google, Gmail or Gchat," said Hu Jia, a prominent Chinese dissident, who has to use a VPN to get round China's ban on Twitter, YouTube and Facebook. VPN or Virtual Private Network software allows users to bypass Internet restrictions.
"These are the only weapons we have to get our message out and the only safe way to do so. The U.S. would never monitor us. They are using it to fight terrorism. It's totally different to what the Chinese government does to listen in on us," he said by telephone.
"Using Chinese sites like Weibo or (online messaging service) QQ is like opening a direct line to the Ministry of Public Security," said Hu, noting that few Chinese dissidents had access to foreign sites like Twitter.
Tibetan activists opposed to Chinese rule in their homeland are similarly unconcerned, since they do not see Washington and Beijing exchanging information any time soon.
"I don't see that happening anytime in the near future with all the other cyber-related issues both countries have," said Lobsang Sither, who works for the Tibetan Action Institute, which focuses on teaching Tibetan exiles how to take advantage of digital communications and non-violent resistance.
Sither, who is based in the Indian town of Dharamsala, said the snooping revelations will however make him redouble emphasis on using encryption technology whenever he talks about or communicates sensitive information.
Nathan Freitas, a New York-based activist who helps Tibetans defend against Chinese cyber-surveillance, said the reports on Prism were nevertheless troubling.
"I'm concerned that from a Western perspective, or at least a U.S. perspective, we are losing some of that moral high ground from which we can pressure China," he said.
"It's just going to be harder to say what they are doing is fundamentally wrong, when maybe it's just becoming statecraft."
© Thomson Reuters 2013
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