In a release, Al Jazeera claimed that for two hours this morning – from 6.30am to 8.30am Doha time – a banner advertisement was replaced with a slogan saying 'Together for the collapse of Egypt', which linked to a page criticising the broadcaster.
A spokesman for Al Jazeera said their engineers had quickly solved the problem.
"Our website has been under relentless attack since the onset of the uprisings in Egypt. We are currently investigating what happened today. While the deliberate attacks this morning were an attempt to discredit us we will continue our impartial and comprehensive coverage of these unprecedented events.
"As with all the other obstacles that have been put in our path, whether that be the detention of journalists, confiscation of equipment, or having our broadcast signal interfered with, we will continue doing our job of reporting on events in Egypt."
Earlier this week Al Jazeera reported that its broadcast signal across the Arab region had been facing interference on a record level.
The network said that it had faced "multiple attempts" to disrupt its coverage from Egypt, "with signals being interfered with on a continual basis, and journalists being banned and detained."
On the Journalism.co.uk Editors' Blog we are trying to track the reported interference with media organisations in Egypt, using Storify to curate Tweets and other accounts of the situation.
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