By Malik Mohamed al-Abdeh
The power struggle between Palestinian rivals Fatah and Hamas has spilled over to the internet with a propaganda war using a popular video sharing website.
Hamas proclaimed the killing of the "traitor spy" Samih al-Madhun
After both groups moved to disrupt each other's television and radio broadcasts, the internet - and YouTube in particular - has become an important medium for disseminating propaganda.
The killing of al-Aqsa Martyrs Brigades commander Samih al-Madhun appears to have been the catalyst for the release of a flurry of videos by both sides.
One video graphically shows the pro-Fatah militant being dragged along and shot by masked gunmen, apparently taken from Hamas's own television station, al-Aqsa TV.
The footage is available at the time of writing, although YouTube's guidelines on graphic portrayals of violence may mean it gets taken down.
Fatah supporters responded with a number of videos commemorating "the hero martyr" Mr Madhun, to stirring music showing him posing with various weapons.
A recurrent theme in videos posted by both Hamas and Fatah is to portray their own people as patriotic and pious, and the other side as treacherous and immoral
One video shows Mr Madhun being dragged next to an image of Israeli soldiers dragging a Palestinian, turning the tables on Hamas which has claimed some pro-Fatah security forces have been collaborating with Israel.
A similar message appears in another commemorative video, showing a mocked-up Israeli banknote with the face of Hamas's Mahmud Zahhar superimposed with the caption: "Two faces of the same currency".
Another frame showed pictures of various Hamas leaders and the caption: "The murderers of Palestine - your fate is the deepest depths of hellfire."
'Let him die'
Hamas supporters then appear to have posted a video showing acts of violence by Mr Madhun's supporters against a group of handcuffed and blindfolded men.
One is wearing a T-shirt that reads "Executive Force", presumably a member of the pro-Hamas security force. He is singled our for repeated beatings and humiliation.
Fatah productions show Madhun as a pious and committed fighter
He is also forced to beg for mercy as a gun barrel is prodded into his chest. A masked gunman asks him: "Who is your master?" The man shouts desperately "Samih, Samih".
It is unclear how the footage may have been obtained, but it seems probable it is the abusers' own recording, uncovered when Hamas gunmen took over their base.
A recurrent theme in videos posted by both Hamas and Fatah is to portray their own people as patriotic and pious, and the other side as treacherous and immoral.
One Fatah video tells Gazans to beware of Executive Force "gangs", accusing them of murder, kidnap, torture and rape. The same video shows Mr Madhun reading the Koran.
Conversely, a Hamas video shows a bearded youth in an all-black uniform, presumably a Hamas member, lying on the ground bleeding heavily and writhing.
Masked men with automatic weapons surround him but do nothing to help. It is not clear who shot him, but one person off-camera shouts "leave him, let him die".
The video appears to have been shot discreetly from a high-rise tower block without the consent of the gunmen.
As well as privately taken footage, both sides have recut news footage to make propaganda points.
A Hamas video entitled "Fatah traitors and agents" shows archive images of Palestinian President Mahmoud Abbas embracing Israeli politicians and generals. Hamas leaders on the other hand are shown embracing Palestinian fighters or on pilgrimage to Mecca.
Fatah propagandists use simple editing technology to make their point
The videos also show the leader of Fatah's parliamentary bloc blaspheming during a TV debate. He is described in a caption as "licentious".
Given that Palestinian Muslims are nearly all from the Sunni branch, some videos seem to be exploiting, or stirring up, anti-Shia sentiments.
In one Fatah video, the dismissed Prime Minister Ismail Haniya is shown embracing President Mahmoud Ahmadinejad of Iran - picking up on Hamas's close links with Shia Muslim Iran to discredit the Islamist movement.
There is also an image showing him embracing a rabbi.
In one commemorative video for Mr Madhun, the late militant is shown in heroic pose with the caption "Vanquisher of the bloody Shia current".
He is also shown alongside the late Iraqi leader Saddam Hussein, whose execution opened a Sunni-Shia faultline, with the caption: "The same killer and the same method".
Hamas touches on the same theme with a video showing the late Fatah-founder Yasser Arafat embracing "the enemies of the Palestinian people" Ayatollah Khomeini, as well as the Pope.