GAZA, March 14 (Reuters) - Some 500 Palestinians, answering a rallying call on Facebook, demonstrated on Monday in Gaza's main square for reconciliation between Hamas Islamists who run the Gaza Strip and President Mahmoud Abbas's rival Fateh group.

The people want to end the division, the crowd chanted as Hamas police watched from the sidelines.

Youth groups that promoted the event on Facebook, a social networking site, said they hoped thousands would join a wider demonstration scheduled for Tuesday in Gaza's Square of the Unknown Soldier and similar rallies in the occupied West Bank.

Organizers said popular revolts in neighboring Egypt and elsewhere in the Arab world had inspired them to act.

Hamas seized the Gaza Strip from forces loyal to Abbas in a brief Palestinian civil war in 2007. Egyptian efforts to reconcile the two groups have made little progress.

(Reporting by Nidal al-Mughrabi; writing by Jeffrey Heller in Jerusalem; editing by Mark Heinrich)