RAMALLAH, West Bank (AP - 12 March) - Israeli forces fired for 10 to 15 minutes from tank-mounted machine guns on a hotel where journalists were photographing armor targeting the al-Amari refugee camp early Tuesday.

No one was injured in the shooting, which sprayed the glass-enclosed stairwell and nearby rooms where about 40 journalists were working. An ABC television camera left running on a tripod when the journalists took cover was hit by seven bullets - one directly in the lens.

The army said the tanks were returning fire from a gunman located somewhere on the upper floors of the hotel and that they were unaware journalists were working from the building. ``It was dark,'' a spokesperson said. An investigation was continuing, the army said.

The reporters said there were no gunmen in the four-story New City Inn, where about 40 television and photo journalists covering the army assault on al-Amari were working from the upper floors.

``If there is a gunman, I would not stay in the building for one minute,'' said ABC television news producer Nasser Atta, who has 13 years experience covering conflicts in the Middle East.

The journalists, working mostly for U.S. and European media outlets, had chosen the hotel some 300-400 yards from the camp's perimeter because it was well-situated to observe the army assault without being caught in the cross fire, Atta said. All the rooms were occupied by journalists, except for four rented to a Swedish company, he said.

He said the tanks earlier had driven by the hotel parking lot containing about 20 media vehicles clearly marked with large lettering.

The journalists recorded the assault on the camp undisturbed for about 40 minutes before a two tanks turned and opened fire from machine guns without warning about 3 a.m. The army surrounded the al-Amari camp in Ramallah as part of raids on several Palestinian towns and refugee camps in recent days aimed at detaining militants and seizing weapons.

``The minute the first round hit, we just all hit the ground,'' Atta said. ``It was a terrifying experience. We did not expect it.''

The fire shattered glass in the stairwell and adjoining rooms, damaging walls and furniture and bursting a water pipe, Atta said.

The firing stopped after the journalists contacted the army to inform officials they were in the hotel, Atta said. The army said it apologized to the journalists for any damaged caused to equipment.

Journalists in the hotel at the time were working for the U.S. networks ABC and CNN, Italy's Rai Uno, Germany's ARD, the Qatar-based satellite broadcaster Al-Jazeera, Reuters, AFP and The Associated Press.

JEBALIYA REFUGEE CAMP, Gaza Strip - 12 March -- Israel intensified its offensive against Palestinian militants - the largest military operation in 20 years - killing 28 Palestinians in raids Tuesday on refugee camps and other targets. Seven Israeli motorists were killed in shooting attacks.

Six of the Israelis were killed when gunmen opened fire on cars near Kibbutz Metsuba, a communal farm near the border with Lebanon. Israeli troops killed two gunman and battled a third for more than an hour. Officials were trying to determine whether the gunmen had crossed over from Lebanon.

That shooting and another in the West Bank that killed one Israeli were apparently in retaliation for Israel's offensive, launched last week after a series of deadly attacks on Israeli civilians.

Israeli security sources said Tuesday that most combat soldiers in Israel's standing army and some reserve troops - a force of many thousands - were deployed in the West Bank and Gaza Strip in the largest-scale operation since Israel's 1982 invasion of Lebanon. In the West Bank town of Ramallah alone, dozens of tanks were patrolling the streets.

Deputy Defense Minister Dalia Rabin-Pelossof, a moderate and daughter of late Prime Minister Yitzhak Rabin, said she expected the strikes to be halted by the time U.S. envoy Anthony Zinni arrives in the region Thursday. Two previous truce missions by Zinni were scuttled by violence.

As the fighting raged, two Israeli Cabinet ministers from the ultra-nationalist National Union party submitted their resignation, saying they felt Prime Minister Ariel Sharon's actions against the Palestinian Authority were not tough enough. Sharon retains a solid parliamentary majority - 75 out of 120 seats - despite the protest.

On Monday evening, about 50,000 Israelis demonstrated in Tel Aviv, calling for stiffer action against the Palestinians. "Defeat Arafat, destroy terror," banners read.

In Tuesday's fighting, the Jebaliya refugee camp - the largest, with 100,000 residents, and a stronghold of the Islamic militant group Hamas - came under heavy Israeli fire from tanks and helicopter gunships during a three-hour incursion. The camp was plunged in darkness when Israeli fire struck a transformer.

Hundreds of Palestinian gunmen exchanged fire with Israeli forces, and at least 18 Palestinians were killed and 75 wounded by Israeli fire, doctors said. Many civilians, some in their pajamas, fled the fighting, moving toward nearby Gaza City on foot and in donkey carts. "They are killing us," said Laila Ayoub, 38, carrying a baby girl in her arms. "They used helicopters to fire on us while we were leaving."

Israeli government spokesman Dore Gold said Israel was showing restraint and "not using the full strength of its air force against the refugee camps."

Israeli tanks also took control of Ramallah and the adjacent Amari refugee camp, where fierce gunbattles were reported. Five Palestinians, including two policemen, two unarmed guards at the parliament building and a taxi driver, were killed by Israeli fire, doctors said.

Several tanks were deployed outside the headquarters of Palestinian leader Yasser Arafat. The takeover came only a day after Sharon announced that Arafat, who had been confined to Ramallah for the past three months by Israel, was free to move in the West Bank and Gaza Strip.

In an angry response, a senior Arafat adviser, Ahmed Abdel Rahman, said Tuesday that "talking peace with the Israelis was a historic mistake." Abdel Rahman said he was confined to his home because of heavy Israeli tank fire.

Israeli troops announced over loudspeakers that boys and men between the ages of 16 and 40 must come out of their homes and surrender to Israeli forces in Ramallah. Local TV stations urged the men not to comply.

Over the weekend, Israeli forces up rounded up nearly 2,000 Palestinians in sweeps of three other West Bank locations, in hopes of tracking down suspected militants. In the Tulkarem refugee camp, troops wrote numbers on the foreheads and forearms of several detainees for identification.

Arafat equated the action with the treatment of Jews in Nazi concentration camps during World War II, when numbers were tattooed on the arms of prisoners as a means of identification.

"Isn't this the sort of thing they used to say the Nazis did against the Jews?" Arafat said of the numbers written on the Palestinians, speaking Monday on Abu Dhabi Television. "So what do they say about these things? Isn't this a new Nazi racism?"

Army officials rejected Arafat's accusation, saying it was aimed at stirring up passions and encouraging his followers to carry out more attacks. The army chief said Tuesday he ordered the practice stopped.

Israeli Foreign Minister Shimon Peres said Tuesday that "we have to be careful not to humiliate (people), not to treat human beings with contempt," adding that he believed Arafat felt humiliated by the Israeli actions.

Israel's offensive began last week, after a string of attacks by Palestinian militants on Israeli civilians. Since the beginning of March, 159 Palestinians and 58 Israelis have been killed, making it the bloodiest period since fighting broke out in September 2000.

Israel's incursion into Jebaliya ended before dawn Tuesday. The Israeli military said it was aimed at finding rockets, destroying weapons factories and arresting suspected terrorists.

Palestinians huddled in terror in cinderblock hovels or fled into the darkness as Israeli tanks rumbled into the Gaza Strip's biggest and most crowded refugee camp.

A Hamas leader, Abdel Aziz Rantisi, threatened bloody revenge. "We have no choice but to kill the occupier, to kill him everywhere, every village and every city. There's no other way to defend ourselves," he said.

In the camp, troops destroyed four buildings, including two metal workshops and the home of Ibrahim Hassouna, a member of the Al Aqsa Brigades militia who killed three Israelis in a shooting attack on a Tel Aviv restaurant last week before being killed by police. The army said the metal workshops produced mortar shells.

Palestinian security officials said Israeli undercover troops commandeered a Palestinian ambulance and drove it into the camp.

Elsewhere in the Gaza Strip, Israeli helicopters shelled a metal workshop and a Palestinian security installation in the Khan Yunis refugee camp, killing four Palestinian civilians, including three members of a family.

In the Deir el Balah refugee camp, Israeli gunboats and helicopters shelled a Palestinian security installation, killing a policeman.