QALQILIYA, West Bank -- The Islamic militants of Hamas won nearly a third of the West Bank and Gaza towns up for grabs in local elections, unofficial results said Friday, cementing the group as a significant political force as Palestinian leader Mahmoud Abbas tries to make peace with Israel.

Abbas' corruption-tainted Fatah movement, which had feared defeat, did better than expected and held on to control over most of the area, winning in 45 of 84 communities. But he will no longer be able to ignore Hamas, which has long opposed negotiations with Israel.

In Qalqiliya, a West Bank town of 45,000 on the frontier with Israel, the green Hamas banner was hoisted over city hall as the group swept all 15 local council seats.

Hamas candidates also won control of the two other biggest towns holding elections, Rafah and Beit Lahiya in Gaza.

The election was the final test for Abbas before parliamentary elections in July that could add to pressures to bring Hamas into the Palestinian administration.

Abbas has encouraged Hamas to transform itself into a political party, hoping this will help him quiet extremists and shore up the truce with Israel.

But Hamas opposes the existence of the Jewish state and its members have staged dozens of suicide bombings, shellings and shooting attacks on Israel in recent years.

Supporters of bringing Hamas into politics, including some Hamas members, argue that will force the group to moderate its approach.

Hamas leaders on Friday tried to allay concerns that they will impose hardline religious views in the communities they now will govern, saying the group will focus on providing better services in the municipalities.

"We are not Iran or the Taliban," said Mohammed Ghazal, a senior Hamas official in the West Bank. "We believe that personal freedom is one of the foundations of Islam."

However, the rise of Hamas -- branded by Israel, the United States and the European Union as a terror group -- poses challenges. Many basic municipal functions, such as electricity supply, telephones and trash collection are handled jointly with Israeli service providers.

The group is an avowed enemy of Israel, although it has agreed to suspend violence as part of a February truce arranged by Abbas.

An Israeli government official, speaking on condition of anonymity, expressed concern that Hamas will emerge as the largest faction in this summer's parliamentary elections and begin influencing Palestinian policy. Hamas has not yet said whether it will seek posts in Abbas' Cabinet after the July vote.

The official said the government would not negotiate with anyone associated with terrorists.

But Israeli analyst Yossi Alpher said it was possible Israel could talk with a Palestinian government that included a more moderate Hamas. "I can conceive of Israel dealing with (Hamas) -- the question is at what point do they give up their arms," he said.

Hamas officials in Qalqiliya predicted that being in power would moderate the group. "We are not dealing with politics, we are trying to improve the daily services of the people of Qalqiliya," said a Hamas spokesman there, Mustafa Sabri.

Qalqiliya is particularly sensitive because of its nearness to the Israeli town of Kfar Saba.

Kfar Saba was once intertwined with Qalqiliya in a relationship that transcended the conflict. Palestinians from Qalqiliya went to Kfar Saba for work and to buy little luxuries. Israelis from Kfar Saba went to Qalqiliya to dine, buy produce and get their cars fixed.

Even today, with a security barrier separating the two towns, many municipal services are still combined. "I say to the Israelis, our neighbors, we are not here to cause problems for anyone. We are here only to give good service to our citizens," Sabri said.

In the southern Gaza Strip town of Rafah, tensions between Hamas and Fatah supporters erupted into violence late Friday.

Thousands of supporters of each party took to the streets throwing stones at each other and gunmen on both sides fired into the air. Hospital officials said six people were wounded by stones.

Thursday's vote was the third -- and largest -- round of municipal voting since December. One more round is to be held later this year.

More than 400,000 Palestinians were eligible to vote Thursday. Turnout was reported at 80 percent in Gaza and 70 percent in the West Bank. Final unofficial results showed Fatah winning 56 percent of the votes and Hamas winning 33 percent, with the remainder going to independents and smaller parties.

According to an Associated Press tally, Fatah won a majority in 45 communities and Hamas in 23. In 16 towns and villages, neither side won a majority, with independents or small groups getting the most votes.

Fatah activists attributed the movement's better than expected showing to its decision to hold primaries and field candidates with broader popular appeal. But Mohammed Horani, a Fatah legislator who advocates sweeping reform, said the party will have to work hard to fend off Hamas in the summer.

Fatah and Hamas both claimed winning more races than the unofficial tally showed. Both sides apparently claimed independent candidates as their own. Fatah demanded a recount in Rafah and Bureij, but did not explain why it suspected irregularities there.