Israel acts against Gaza militants

This is the farthest a rocket has reached since 2000

Israeli Prime Minister Ariel Sharon has ordered the army to take "all necessary steps" against Palestinian militants after they fired a rocket into an Israeli city.

"I have instructed the minister of defence to take all necessary steps to avoid such actions in the future," he told correspondents after the rocket strike on Ashkelon, which caused no damage or casualties.

An explosion in the Gaza Strip killed one Palestinian and injured three others later on Thursday. The cause of the blast is not known but Israeli helicopters had been flying over the area.

Earlier, Israeli armed vehicles cleared vegetation from an area of the northern Gaza Strip from where the rocket was fired to prevent squads from taking cover.

It's crossing a red line...This is an alarming reality for us Foreign Ministry spokesman Jonathan Peled Analysis: Power struggle

The strike into Ashkelon's industrial zone was the furthest a rocket had been fired since the Palestinian uprising for statehood began in 2000.

The Palestinian militant group Hamas had earlier rejected calls by Palestinian leader Yasser Arafat for militant groups to renew the truce they abandoned last week.

Hamas political leader Abdel Aziz al-Rantissi said the group would not consider a truce while Israel continued targeting its followers, and warned against any attempt at a crackdown by Palestinian security forces.

Palestinian Foreign Minister Nabil Shaath told the BBC that by rejecting Mr Arafat's appeal the militants were putting Palestinians "in danger".

"The roadmap is the only proper road we have back to peace," he said.

'Red line'

Hamas and Islamic Jihad both called off a seven-week-old truce last week after Israel killed Hamas co-founder Ismail Abu Shanab in retaliation for the suicide bombing of a Jerusalem bus that left 21 people dead.

Sharon: Tough words

Palestinian officials told Reuters news agency Palestinian security forces had rushed to the area from where the rocket had been fired to rein in Hamas militants to prevent further launchings.

"There was a chase and a shootout," a Palestinian security official told the agency.

Israeli officials said Thursday's attack may have breached a "red line" necessitating a major military response.

"It's crossing a red line...This is an alarming reality for us," Foreign Ministry spokesman Jonathan Peled said.

The road map requires Palestinians to end violence and Israel to pull back forces from occupied territory to pave the way for a Palestinian state in Gaza and the West Bank by 2005.