GAZA, 9 December — Israel renewed its military campaign against Palestinian targets yesterday, sending helicopter gunships to attack security buildings in the Gaza Strip despite Palestinian President Yasser Arafat’s new pledge to crack down on activists.

Two US-made Apache attack helicopters fired nine missiles into three buildings in one compound in Rafah, on the border with Egypt, but there were no casualties as the buildings had been evacuated, a security source said.

“There were at least nine missiles aimed at the Force-17 building and military intelligence office in Rafah, those two buildings were destroyed and there was damage to the police headquarters,” the source said.

An electric power transformer was also blown up and Rafah was completely blacked out, he added. Force-17 is Palestinian leader Arafat’s elite bodyguard unit.

It was the second round of airstrikes against Palestinian security targets in the Gaza Strip in as many days, and the fourth this week.

The attack came hours after a new round of US-brokered security talks which both sides described as “difficult”.

“This is a war against the Palestinian people, an unfair war,” said one Palestinian official, adding that the latest attack was “against efforts of peace the Americans and the rest of the world are trying to achieve”.

Indicating the difficulty on reaching agreement on how to quell the violence, a senior Palestinian security official said Friday’s talks, brokered by US envoy Anthony Zinni, almost degenerated into a brawl.

“They were very difficult talks, and the Israelis were trying to dictate and give us orders. There was almost a fist fight and we were shouting at each other,” the official said. An Israeli official, who also described the meeting as “difficult”, said Israeli security chiefs rejected a Palestinian request that they ease the pressure on the occupied territories until Arafat clamped down on activists. Palestinians said they were still awaiting a response to specific demands, expected at a meeting scheduled for today.

The Palestinian official said the demands included stopping the Israeli assassination of activists, ending the blockade and re-occupation of Palestinian areas and halting attacks on Palestinian installations so a campaign of arrests can continue.

In a later development Israeli tanks destroyed two Palestinian police posts near the Gaza Strip city of Rafah.

"Israeli tanks made another incursion near Rafah, between Rafah and Khan Younis, on the main road east of Morag settlement, and they destroyed two national security police posts," he said.

In the northern West Bank, a 12-year-old Palestinian boy was seriously wounded during clashes with Israeli soldiers, a hospital official said.

Yasser Al-Kasbeh was hit in the head with a rubber-coated steel bullet near the Palestinian refugee camp of Kalandiya as he threw stones at a group of young soldiers manning a checkpoint, witnesses and the hospital official said.