HIGHLIGHTS: Battles Rage on in Gaza||Israeli House-to-House Arrests in Jenin||Eight Palestinians Wounded in Various Clashes Across the Territories ||Occupation Forces Enter Tulkarm||Arafat and Jordanian Foreign Minister Condemn Israel's Reoccupation Policy||STORY: Israeli tanks rolled into the West Bank city of Ramallah on Monday, witnesses said, surrounding the headquarters of Palestinian President Yasser Arafat in the latest phase of Israel's expanding crackdown.

The witnesses said an explosion could be heard as at least one column of some 20 armored vehicles moved through the city.

HAMAS FOUNDER ARRESTED

In an apparent fresh response to that pressure, the Palestinian Authority placed the founder and spiritual mentor of the Islamic militant group Hamas, Sheikh Ahmed Yassin, under house arrest in Gaza City early on Monday. (Read photo caption)

"It was decided, starting from tonight, to impose house arrest on Sheikh Ahmed Yassin to safeguard the ultimate national interests of the Palestinian people," a Palestinian security official told Reuters.

"The decision was issued from high up, from President Yasser Arafat," he said.

The last time Yassin was placed under house arrest, in December, a Hamas supporter was killed in the ensuing clashes with Palestinian police in Gaza City. That arrest order was lifted after Yassin agreed he would not make media appearances and that he sends his armed bodyguards away from his home.

Palestinian security forces arrested about a dozen activists of Hamas in the Gaza Strip on Sunday, a Palestinian security source said. The source said most of those detained were field-level activists and not top political leaders.

However, a source told Reuters an arrest warrant had been issued for Abdel Aziz al-Rantissi, a senior Hamas official who has been arrested and released several times by the Palestinian security forces.

"The Authority is very serious this time to continue this campaign of arrests in order to ensure stability and a respect to the one authority, the Palestinian Authority," the source said. He said security forces had also been ordered to put an end to the shows of strength by armed activists in Gaza streets, which embarrass Yasser Arafat at a time when he is under intense international pressure to crack down on them.

Hamas condemned the detention of its activists. "We view the arrest campaign as a grave step that harms the national unity at a time when we all need to be in one trench facing the occupation," Ismael Abu Shanab, a senior Hamas official, told Reuters. Those arrested included Jamal Saleh, leader of an Islamic political party, which is an offshoot of Hamas, and Mohammed Shahab, a well-known Islamic activist.

The security source said more arrests would be made.

ISRAELI ATROCITIES CONTINUE

Palestinian Resistance men and occupation army soldiers were reported engaged in firefights throughout the Gush Katif bloc at the southern end of the Gaza Strip Monday morning.

Anti-tank rockets were reportedly fired at a tank at a position near the internationally illegal settlement of Ganei Tal.

There are no reports of injuries or damage.

Elsewhere in the territories, a 20-year-old Palestinian Resistance man was killed and several others were wounded after a tank returned fire after at them near Tulkarm, earlier this evening.

Israeli occupation troops killed a Palestinian policeman and wounded two others in an early morning gun battle near Jenin on Sunday.

Israeli troops and armor entered Qalqilya town and arrested three suspected militants. Palestinian sources reported at least six other arrests elsewhere in the West Bank.

The Israeli occupation army has swept through a series of West Bank towns and cities on search-and-arrest operations since two Palestinian bombings and a gun attack on an internationally illegal Jewish settlement last week.

The occupation army said it was calling up a brigade of reservists who would be trained and join troops in "the war against Palestinian terrorism." It did not give a precise number, but Army Radio said thousands would be mobilized for at least a month.

Israeli occupation troops conducted house-to-house searches for activists in Jenin. There were no immediate reports of arrests.

In Gaza strip, three Palestinians were wounded when Israeli occupation troops fired on their car near the Nezarim settlement, a Palestinian security source said, according to AFP.

ARAFAT & THE JORDANIAN FOREGIN MINISTER CONDEMN ISRAELI REOCCUPATION POLICY

Arafat accused Israel of intending to take over all aspects of Palestinian life in the occupied areas, including civilian affairs.
"This situation is very serious and difficult," Arafat said Sunday after meeting European officials at his offices in Ramallah.

"It is clear that this is a continuation of the occupation in our towns and refugee camps."

Arafat, whose compound has been under Israeli siege on and off since last December, has made only brief day trips outside Ramallah during that time. He has not been to the Gaza Strip or anywhere outside the Palestinian territories.

Jordanian Foreign Minister Marwan Muasher said after meeting with Arafat that it is "unacceptable to reoccupy Palestinian cities and to turn the clock back, to return to the civil administration in the West Bank, which is a military administration."

Israeli officials have stressed the potentially long-term incursions would not lead to reestablishment of Israel's military administration, which presided over Palestinians until the creation of autonomous areas began in 1994.

PHOTO CAPTION

The Palestinian authority has put Hamas founder Sheikh Ahmed Yassin under house arrest on June 23, 2002. Ahmed Yassin speaks during an interview with Reuters in his home in Gaza Strip in this May 23, 2002 file photo. (Ahmed Jadallah/Reuter