The Islamic Resistance Movement, or Hamas, will stage a big rally on Sunday in Gaza city to celebrate its 21st anniversary.
The rally, which starts at 13:00 local time(1100 GMT), will be attended by senior Hamas leaders and members of deposed Hamas government that has been ruling Gaza Strip since June 2007.
It will be the second anniversary rally after Hamas took control of the coastal enclave where used to be ruled by its rival Palestinian President Mahmoud Abbas' Fatah movement.
Since early Sunday morning, local mosques have been calling on Hamas supporters to head for the "Green Katiba," a place named by Hamas after it held previous celebration.
To facilitate the flow of people to the Katiba, Hamas sent buses in front of every mosque across Gaza Strip, deployed its security men on every corner.
At the Katiba, a square located near pro-Fatah al-Azhar university and close to the major security compound previously ran by the Palestinian National Authority, bearded youths are putting the final touches on the stage of the rally.
"What we are doing here is a service for our movement," said one of the youths as he watched a large poster of Hamas' spiritual late leader Ahmed Yassin on a four-story building.
Deposed Hamas Prime Minister Ismail Haneya plans to deliver a speech in front of the crowds that the organizers said the number is expected to be "hundreds of thousands."
Mahmoud Zahar, a Hamas hard-line leader, said that the Islamic movement "developed itself militarily, politically and publicly."
Hamas and Israel observe a shaky ceasefire that is to end on Dec. 19 with supporters wait to hear a decision about the agreement as they believe Israel did not respect it.