JERUSALEM — The contentious issue of land expropriation has spurred one of the worst clashes in recent years between Israeli Arabs and police.

Scores of Palestinians were injured Sunday and Monday in pitched battles between stone-throwing protesters and police firing tear gas and plastic bullets in the town of Umm el-Fahm and along parts of the Wadi Ara highway, a central artery in central Israel.

Umm el-Fahm is about 25 miles southeast of Haifa.

The clashes occurred after Israeli Arabs gathered to protest the confiscation of mostly farmland from around Umm el-Fahm and the nearby village of Muawiya for use as army training grounds.

Sunday and Monday's clashes were followed by a one-day general strike Tuesday called by the Israeli Arab leadership to protest what they called brutal behavior by the police on the previous days.

The army spokesman confirmed that the army had confiscated about 125 acres for training purposes, but had also returned to local residents about 500 acres that had been expropriated in the past.

Sunday's confrontation began after police tried to dismantle a protest tent set up by local farmers in fields around Muawiya. Police charged that the tent was placed provocatively inside the training area's fire zone.

Around 10 a.m. police moved in to demolish the protest tent and evict the two local farmers who were demonstrating there. The eviction passed quietly, but the incident sparked a wave of rioting that closed the road from the Megiddo junction to south of Umm el-Fahm for most of the day.

About 400 local teens and adults rioted, including Mayor Sheikh Raed Salah, head of the radical wing of the fundamentalist Islamic Movement.

Sunday's riots left about 80 protesters and 27 police injured. Some of the police officers were beaten by demonstrators with sticks and others were hit by stones.

During the clashes, Salah was injured and claimed he was punched in the stomach by a police officer. He was taken to a hospital, where he was held for observation.

Before he was injured Sunday, Salah charged that the government was expropriating the land with a hidden agenda: to build a new Jewish city of Irron with 300,000 residents.

The confiscation of Arab lands to build the town of Karmiel in the Galilee in the late 1970s led to riots in March 1976, which left six Arab protesters dead.

Salah's injury fueled the demonstrators who increased the rain of stones, bottles and other objects. Police reinforcements equipped with riot gear, including tear gas, rubber bullets, and specially trained horses, were brought in.

As many as 800 police became involved. Heavy vehicles were used to clear away blazing garbage cans and other riot debris.

The confrontation continued the next day, despite an agreement reached Sunday night with Israeli Arab leaders. The agreement will allow farmers to tend their olives groves and cultivate their crops on the disputed land until January.

Tensions flared again Monday when police prevented local Arab youths from disrupting traffic on the main highway separating the towns of Hadera and Afula.

Some 40 Israeli Arabs were injured on Monday, including Ahmed Tibi, Palestinian Authority leader Yasser Arafat's adviser on Israel affairs. More than 20 Israeli Arabs were arrested.

Arab leaders, including Knesset members Hashem Mahameed of the Hadash Party and Abdul Malik Dahamshe of the Democratic Arab Party, accused the police of using excessive force.

Some local residents accused police of firing live bullets and of chasing students into a school after stones and Molotov cocktails were thrown from the building.

"The behavior of the police and border policemen towards Israeli citizens was very reminiscent of what happened in the West Bank," Mahameed said. "I asked myself whether the security forces of Israel are trying to reconquer the Umm el-Fahm area."

Alek Ron, an Israeli police commander, put the blame for the violence on the demonstrators and said police had reacted only with necessary force. Ron also asserted that calls had been sounded from local mosques which had incited residents.

He added that intensive negotiations had been going on with local farmers and Israeli Arab leaders over the land issue long before the eviction, including offers of compensation and alternative land.

"For three weeks this shack had, until this morning, been there as an illegal building in a military firing zone. There are no such illegal buildings in any other IDF firing zone," he said.