(AP Photo /Nasser Ishtayeh)
The bitter rivals have been buying, smuggling and building weapons for months trying to gain an edge, but they have held back from all-out battle and find themselves in a stalemate.
That leaves many Palestinians with grim hopes that a power-sharing deal still can be worked out between the Islamic militants of Hamas and the more moderate President Mahmoud Abbas of Fatah.
Bursts of violence have alternated with periods of tense calm since the factional fighting erupted in December following the collapse of Hamas-Fatah coalition talks and Abbas' threat to call early elections.
Experts expect the pattern to continue. "They are equal parties," analyst Nasser Al Lahham said. "No one can cancel the other out."
(Muhammed Muheisen ~ Associated Press)
Clashes involving mortars, grenades, bombs and assault rifles have erupted spontaneously, without clear objectives or central command, raged for a few hours, then suddenly fizzled.
Saudi King Abdullah offered Sunday to mediate between the rivals. Both sides welcomed the offer but did not say when talks might be held. Ghazi Hamad, spokesman for the Hamas-led government, said the Islamic group was in talks with Egyptian mediators.
Fatah gunmen killed a Hamas activist in Khan Younis on Sunday and a Hamas security force member in Gaza City early Monday. Another gunman, whose affiliation was not immediately known, and a 45-year-old civilian were also killed, hospital officials said.
Several kidnappings also were reported in the factional conflict. The most brazen was in the West Bank city of Nablus, where Fatah gunmen walked into a bank and dragged out a local Hamas leader.
Hot spots in the fighting include the headquarters of Abbas' security forces, Hamas-run mosques and the homes and offices of leaders from both sides, where guards hunker down behind concrete barriers and piles of sandbags.
Traffic jams are getting worse by the day in Gaza City's already crowded streets because more and more roads are being closed to motorists by the rival security forces.
Neither side is using all of its firepower because they are giving coalition talks another chance and because they fear risking defeat in an all-out confrontation, said Mouin Rabbani, a Jordan-based analyst for the International Crisis Group, an independent think tank.
Each side can count on thousands of armed men. Most members of Palestinian security forces are loyal to Abbas, while Hamas last year set up its own 5,600-man militia. Each also has a military wing -- Fatah's Al Aqsa Martyrs' Brigades and Hamas' Izzedine Al Qassam Brigades.
Hamas is getting funds from Iran and other Islamic supporters worldwide, while the Bush administration has asked Congress to approve $85 million in aid for Abbas' troops.
Israeli analyst Shlomo Brom, a retired army general, said the U.S. shouldn't count on Abbas being able to defeat Hamas militarily. "That is not going to happen, because Hamas is a political movement that enjoys great support among the Palestinians," he said.
The Gaza muddle will likely continue, Brom added. "The probability of a full-scale war is low, because the two parties understand the consequences and they understand there will be no clear winner."
Both sides began preparing for the possibility of a big battle after Israel left the Gaza Strip in September 2005 and the arms race intensified after Hamas won legislative elections a year ago and took control of the Palestinian government.
Rifles, missiles, ammunition and explosives have been pouring into Gaza through tunnels under the border with Egypt, reaching both Hamas and Fatah, security officials and weapons dealers say.
In a climate of increasing lawlessness, Gaza clans also have stocked up on weapons, two weapons dealers in the southern Gaza border town of Rafah said Sunday, speaking on condition of anonymity for fear of arrest.
Higher-quality Russian- and Iraqi-made Kalashnikov assault rifles are no longer available, and Egyptian or Chinese models sell for up to $2,300, almost double what they cost a year ago, the dealers said. Kalashnikov bullets now cost $3.30 apiece, up from $2.30, they said.
Abu Suoud, 32, a Fatah gunman in Rafah, said his group is hoarding ammunition, and no longer wasting bullets by firing into the air at weddings and funerals.
"We save each bullet for the battle," he said.