The Twitter stream, which last month proved to be a vital link for anti-government protesters in the Middle East, quickly turned into a worldwide forum for comfort, heartbreak and hope for Japan's quake-stricken residents.
Social-networking powerhouses Twitter and Facebook once again became important communications tools in a natural disaster.
Live reports from Japanese television networks instantly beamed startling images of the 8.9-magnitude quake and resulting tsunami to the world. But personal communications were reportedly spotty in Japan, so individuals also turned to Twitter and Facebook.
Facebook and Twitter were filled with prayers and support from around the world. In one tweet, President Obama sent "condolences to the people of Japan, particularly those who lost loved ones in the earthquake & tsunamis. U.S. stands ready to help."
Relief agencies immediately turned to social networking to solicit much-needed donations.
Causes, a San Francisco nonprofit, launched new campaigns on Facebook to help raise money for a variety of services, including the American Red Cross, Catholic Relief Services and Oxfam USA.
The organization specializes in grassroots social media fundraising for about 500,000 causes. It has about 150 million users of its Facebook fundraising application, said Matthew Mahan, the group's vice president of social impact.
As of Monday afternoon, Causes visitors had "donated over $150,000 to various nonprofits serving in Japan," its website reported, noting "we're blown away by the outpouring of generosity on the part of our global community."
Through social media, Mahan said, people who show interest in a cause become "more involved at a deeper level and are more likely to open their pocketbook or volunteer to get out and knock on doors."
The American Red Cross is raising money through a mobile phone texting campaign, which "Star Trek" star George Takei helped publicize to his Twitter followers: "Today we are all Japanese. Give $10 to help. Text REDCROSS to 90999."
Another group, the Mobile Giving Foundation, launched a similar text donation campaign on behalf of several charities, including the Save the Children Federation.
But McAfee Inc., Intel Corp.'s computer security unit, warned potential donors to be wary of tiny URLs posted on social networks because they may lead to phishing or scam sites. One site that proved be a scam appeared just two hours after the Japan earthquake.
McAfee suggested these tips:
-- Type the URL directly into a browser to verify that the organization is actually a registered charity.
-- Do not respond to pitches that arrive by unsolicited e-mail, "especially those sounding overly urgent or desperate."
-- Avoid clicking on ad banners that solicit donations.
-- Support known major international organizations such as the Red Cross.
Contact Benny Evangelista at bevangelista(at)sfchronicle.com. The Scripps Howard News Service contributed to this report.
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