Facebook Inc said on Tuesday that it is investigating a rash of unsolicited graphic images that hit some users' accounts this week.
The images, Internet links and videos depicting pornography and violence have hit some people's Facebook newsfeeds in recent days.
"We have recently experienced an increase in reports and we are investigating and addressing the issue," Facebook spokesman Andrew Noyes said in a statement e-mailed to Reuters.
"Protecting the people who use Facebook from spam and malicious content is a top priority for us and we are always working to improve our systems to isolate and remove material that violates our terms," he added.
Facebook and other "Web 2.0" web sites are easy targets for such attacks because they pull in a lot of content from outside sources, according to online security expert Paul Ferguson.
"It seems every other day there is some new Facebook 'threat,' but this is just the new reality of Web 2.0 and social networking," Ferguson said. "It is 'low-hanging fruit' for criminals."
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