The websites of the Arabic news network, Al-Jazeera, were hacked on Tuesday, apparently by a group sympathetic to the Syrian regime.

Al-Jazeera's English and Arabic websites were affected by the hack, made by a group calling itself al-Rashedon, or "the guided ones".

"This is a response to your position against the people and government of Syria, especially your support of the armed terrorist groups and spreading false fabricated news," the group said in a statement blanketing aljazeera.net. "Your website has been hacked, and this is our response to you."

In a statement, the network said its external services had been "compromised". It added: "The company that operates them quickly resolved this, though some users may continue to experience issues for a while longer. We thank our online community for their patience and support."

Commentators said they were not familiar with the group that claimed responsibility. "I have not heard of this group before," wrote Ahmed Al Omran, a Saudi journalist and blogger, in an email to the Guardian. "Previous attacks of similar nature have been claimed by the Syrian electronic army."

Aaron Zellin of the Washington Institute for Near East Policy, a thinktank based in Washington DC, said: "I think the hackers were just trying to make a statement and get their voices heard. It will get them attention, if just for a few days." Zellin said there were suggestions that the hackers may be a cyber arm of the Shabiha militia loyal to Syrian president Bashar al-Assad, but that such a connection was difficult to prove.

Since the start of the Arab spring, al-Jazeera has made a name for itself as one of the leading news organizations covering the region's instability. Unlike some other state-controlled media, al-Jazeera has been known for aggressive coverage of dictators and oppressive regimes. But it has also been accused of inconsistency and bias.

A number of staff resigned from al-Jazeera earlier this year, accusing it of being biased against the Syrian regime but in favor of Bahrain, a Gulf state neighbor of Qatar, where the network is based.

Al-Jazeera is funded by the Qatari government; critics say it follows its sponsor's foreign policy objectives, although the broadcaster says it is independent of government control.

"Over the past year al-Jazeera has become more sectarian and more biased in what they cover and what they don't cover," said Zellin. "They don't cover issues that don't fit the Qatari foreign policy narrative."

• This article was amended on 5 September 2012 to correct the spelling of the name of the Saudi journalist Ahmed Al Omran.