A copy pf the poster, taken from the Israel Defence Forces official Tumblr blog.

A copy of the poster, taken from the Israel Defence Forces official Tumblr blog.

Footage of the assassination of a Hamas leader in a missile strike in the Gaza Strip was pulled from YouTube overnight for breaching the popular video-sharing website's terms of service.

But just hours later, the 10-second video – which shows the moment Ahmed Said Khalil al-Jabari's vehicle exploded as it drove through Gaza city – was reinstated and YouTube said its removal was a mistake.

The battle being waged on the ground continues to be fought fiercely online, as both Hamas and the Israel Defense Forces try to get the upper hand in the propaganda battle and deliver their messages directly to readers.

Israeli military officials live-blogged and live-tweeted their offensive in the Gaza Strip on Thursday (AEST), posting video of the fatal strike on the Hamas military leader's vehicle within hours, and later re-tweeting the link "in case you missed it".

That prompted a volley of return tweets from Hamas's military wing, the Al-Qassam Brigade, which directed one tweet directly to the Israeli Defense Forces Twitter account: “Our blessed hands will reach your leaders and soldiers wherever they are (You Opened Hell Gates on Yourselves)."

But the online stoush has raised questions about what role social media should play in military campaigns.

The 10-second video posted by the IDF showing al-Jabari's assassination was pulled from YouTube, the world's largest video website, for overstepping the mark.

It was replaced with the message: "This video has been removed because its content violated YouTube's Terms of Service. Sorry about that."

YouTube's Terms of Service state that "graphic or gratuitous violence is not allowed. If your video shows someone being physically hurt, attacked, or humiliated, don't post it.

"YouTube is not a shock site. Don't post gross-out videos of accidents, dead bodies or similar things intended to shock or disgust."

However hours later, the video was reinstated and YouTube said its removal was a mistake.

In an email to the technology website All Things Digital, a YouTube spokeswoman said: “With the massive volume of videos on our site, sometimes we make the wrong call. When it's brought to our attention that a video has been removed mistakenly, we act quickly to reinstate it.”

YouTube users were believed to have “flagged” the video, which triggered a review process and a YouTube employee decided to take it down, All Things Digital said. Later, that decision was overturned and the video was put back up.

Overnight both sides continued the propaganda battle in social media.

The IDF tweeted a poster, which also featured on its official Tumblr blog, of a target over a group of people alongside the words: "Israeli civilians are Hamas' target."

It also tweeted an image of a baby "wounded today from a rocket attack in #Israel".

Alqassam Brigades also tweeted an image of a baby purportedly killed in the strikes.

"#Israel's military kills #Palestinian children in cold blood in #Gaza, shelling civilians & populated areas #Humanrights," Alqassam Brigades tweeted.