Gaza, May 13 (Xinhua) -- Islamic Hamas movement on Sunday called on people to join the largest ever rallies and marches organized in eastern Gaza Strip on Monday.

Hamas called on people to keep sticking to their right of return and join the great marches on May 14 and 15, saying that rallies on Monday will also protest the U.S. decision to move its embassy from Tel Aviv to Jerusalem.

"The marches will be also rejecting the unjust and unfair siege that had been imposed on the Gaza Strip for 12 years," Hamas said, calling on Israel to lift the blockade and on the Palestinian Authority to end its sanctions it imposed one year ago on Gaza.

Since March 30, the Palestinians have been organizing protests, demonstrations and rallies calling it "the Great March of Return." They erected tents and carried out various activities in the areas of eastern Gaza Strip, close to the border with Israel.

Meanwhile, Israel warned that its army will harshly respond and strike on Hamas infrastructure all over the Gaza Strip, in case of masses of demonstrators who try to cut the fence of the border and infiltrate into Israel, according to Israeli media.

Gaza Health ministry said in an official statement that 49 Palestinians were killed and more than 8,000 injured by Israeli army gunfire since the beginning of the marches.?