They're all a Twitter about the flotilla.

It may still be anyone's guess when a small international convoy of vessels carrying pro-Palestinian activists and aid will set sail from Greece to the Gaza Strip in a challenge to Israel's naval blockade of the territory run by Hamas Islamists.

But, mindful of the bloodshed at sea and global outcry that marked a similar event last year, the opposing sides are already battling for hearts and minds in the social and mainstream media.

An array of Facebook pages, websites and tweets posted by organizers of Freedom Flotilla II (www.freedomflotilla.eu), say they are on a humanitarian mission of peace. Waging its own public relations campaign, Israel says the activists could be plotting violence.

A text message sent to reporters by Prime Minister Benjamin Netanyahu's office (www.facebook.com/IsraeliPM) on Monday quoted unnamed Israeli officials as saying flotilla organizers might use chemicals against Israeli troops sent to intercept the convoy.

The next day, the Israeli military, which is under orders to prevent the ships from reaching the Gaza Strip, went on the record with the same accusation.

The US Boat to Gaza used its Facebook page (www.facebook.com/USBOATTOGAZA) and tweets to challenge the allegation. The group, which has dubbed its vessel The Audacity of Hope, said Israel was fabricating horror stories about hundreds of unarmed civilians in the flotilla.

Israeli Defence Minister Ehud Barak said in a television interview later on Wednesday that while it was not known what the ships might be carrying, forces were readying for all eventualities.

I am sure the (military) is better prepared than in the past. This is not a sea cadet ride or a pleasure cruise and in any event we must be ready for all scenarios ... The working assumption for the forces is that they could meet very violent resistance, Barak told Israel's Channel 2.

Israel says the blockade, enforced since 2006, is aimed at stopping more weapons from reaching Hamas, a militant group shunned by the West over its refusal to recognize Israel and renounce violence. Palestinians and their supporters say the measure is illegal and constitutes collective punishment.

HIGH STAKES

The stakes are high -- a year ago, nine Turkish activists, including a dual U.S.-Turkish national, were killed in clashes with Israeli soldiers who raided a Gaza-bound convoy in the eastern Mediterranean.

Israeli-Turkish relations neared breaking point after the bloodshed and an international outcry led to Israel easing its land blockade of the Gaza Strip.

Israel has urged foreign governments not to let the new convoy of about 10 ships get under way. Organizers in Athens have accused Greece, where some of them are docked, of raising bureaucratic obstacles and bowing to Israeli pressure.

Flotilla groups and Israel have also used YouTube to make their case -- in at least one instance in a video that looks to have been a hoax.

Organizers of the convoy said the propeller of one ship was cut in Piraeus harbor near Athens on Monday, and they accused Israel of sabotage. A video uploaded to YouTube by digital flotilla showed the damage and an interview with the boat's captain.

Another YouTube video featured a man who identified himself as Marc, an American gay rights activist (www.youtube.com/watch?v=vhmBbGFJleU&feature=player_embedded). He said he had offered flotilla organizers the support of a network of gay activists but they had turned him down.

It was hurtful, he complained, accusing Hamas of homophobia. Israel's Government Press Office and the Foreign Ministry (www.facebook.com/IsraelMFA?v=wall), as well as an intern in Netanyahu's office linked to the video on their Twitter feeds.

A pro-Palestinian website later said the video, which appeared to have been professionally made, was bogus and identified the man as a Tel Aviv actor.

A photo of the actor on an Israeli celebrities website matched the man in the video.

(Editing by Alastair Macdonald)