The online hacktivist collective Anonymous claims it has knocked almost 500 Israeli websites offline in a coordinated cyber-attack in support of the people of Palestine.

The group has also published the emails, passwords and phone numbers of Israeli officials as part of the OpIsrael campaign.

Also called OpIsraelBirthday, the cyber-attacks were launched on 7 April to coincide with the eve of Holocaust Remembrance Day, with most websites knocked offline by distributed denial of service attacks (DDoS).

The websites targeted are predominantly Israeli government and administration websites. However some of the websites which Anonymous claim to have attacked - such as the Israel Agricultural Research Organisation - are currently online.

Leaked emails and phone numbers

In addition ot trying to knock websites offline, one of the groups spearheading the attack - known as AnonGhost - has published what it claims are emails, passwords and phone numbers of Israeli government officials.

According to a video posted on YouTube, the reason for the attack is Israel's attacks on the people of Gaza:

"The further assault on the people of Gaza, who have been flooded by your sewage, terrorised by your military apparatus, and left to die at the border while waiting for medical attention will not be tolerated anymore."

The group has called on supporters around the world to take part in the attack, posting links on Twitter and other social media channels to websites which give details on how to take part in the attacks and which websites to target.

Sabu

Some in the collective have warned however that this will leave many of those taking part open to identification and possible prosecution, especially if they have limited technical knowledge and are unable to mask their IP address.

Some of the more conspiratorial members of Anonymous have even suggested this backs up rumours that the US government is using former LulzSec hacker Sabu (aka Hector Monsegur) to instigate OpIsrael.

Reports also suggest that pro-Israeli hackers have launched a counter-attack against the OpIsrael website to post pro-Israeli messages on the site. The website is currently offline.

OpIsrael

This is just the latest cyber-attack by Anonymous groups targeting Israel, with one under the same OpIsrael banner last April promising to "wipe Israel off the face of the internet" - a claim which failed to transpire.

In November of 2012 the group once again launched an OpIsrael campaign in retaliation for attacks on Gaza, claiming to have defaced 87 websites.