A video that includes clips of Gilad Shalit smiling during a barbecue while in Hamas captivity was released on Sunday by the Iz al-Din al-Qassam Brigades, the military wing of Hamas.

Shalit is also seen eating, watching TV and reading letters from his family in the video, which is clearly intended to highlight Hamas' humane treatment of Israeli prisoners.

The video focuses on a special unit of its military wing called the Shadow Unit, which it says was responsible for guarding Shalit while he was a Hamas captive. The unit, the video says, "knows Shalit well."

Among the unit's duties, according to the video, are "to guard enemy captives held by the al-Qassam Brigades, to hide them and to thwart enemy attempts to find them."

The video says that the unit "treats enemy captives honorably, in line with the rules of Islam, and provides for their needs, taking into account the treatment given to the prisoners of the resistance in the hands of the enemy."

Members of the unit "stay in the shadows, away from the light," according to the video, and they operate in complete secrecy.

The clandestine unit is being publicized for the first time under the authority of the Hamas leadership, according to the video. A spokesman says the unit was established a decade ago and its members are "chosen from all the units of the military branch."

The timing of the video was not coincidental and it was aimed at both an intra-Palestinian audience, particularly in the Gaza Strip, and Israeli public opinion, a diplomatic source in Gaza told Haaretz.

"There's no doubt that Hamas, including its military wing, feel that things aren't moving," the source said. "As far as Israel is concerned, they think that they might spark some movement in Israeli public opinion by emphasizing the fact that previous contacts regarding prisoners and soldiers missing in action have all halted."

Internally, the source said, Hamas has no diplomatic or military achievements to show right now and the blockade on Gaza has not been lifted.

"The port and the airport are already old news, the talks about reopening the Rafiah crossing are stuck, the negotiations with the Palestinian Authority aren't going anywhere and there are tens of thousands of bureaucrats without salaries and not making a living in Gaza," the source said.

"What's left, particularly following the events of recent months, is the hope that they'll be able to inspire the Palestinians by releasing details about an elite unit."

Shalit's family said that Gilad's captors "will use any means necessary to present a distorted image, which reflects in no way the five years of captivity, loneliness and daily fear [Gilad Shalit] suffered to stay alive."