Close on the heels of Lockheed Martin admitting that it had been hacked, it has emerged that the Public Broadcasting Service (PBS) has been hacked and login and password information pertaining to employees as well as outside users of the site have been compromised.

A Twitter user called @lulzsec published site maps, database structures plus thousands of logins and passwords of employees and journalists who used the site, ABC News reported.

It has been reported that the ‘Anonymous’ hacking group attacked PBS, known for programs like 'Sesame Street', after it aired a documentary called ‘Frontline’ that criticized whistle-blower website WikiLeaks and published posts by Bradley Manning, who is in U.S. custody for allegedly leaking out vast tracts of U.S. military documents to Julian Assange's site.

The hackers also posted a meme-based calling card saying Free Bradley Manning. F*** Frontline, according to the report.

The ABC News report says email addresses, usernames and passwords of more than two thousand users have been published online. While we couldn't confirm that they were valid, there is a strong air of legitimacy about them.

Bradley Manning is a 23-year-old U.S. Army private who was working in Iraq as an army intelligence analyst when he was arrested in May last year after being accused of copying several thousands of military documents and passing them on to WikiLeaks. Manning had been charged with transferring classified data and delivering national defense information to an unauthorized source.