Palestinian militants have fired a second rocket at the Israeli city of Ashkelon - as Israeli tanks advanced in the Gaza Strip in an effort to halt such attacks.

Israeli officials say no one was injured in the rocket attack late Wednesday.

Meanwhile, Palestinians said Israeli tanks advanced in northern Gaza to a former Jewish settlement reportedly used by militants to launch rockets.

Earlier today, Israeli Prime Minister Ehud Olmert and his security cabinet approved plans for troops to push farther into the Gaza Strip and create a buffer zone to prevent the rocket attacks.

The rocket attack late Tuesday on Ashkelon marked the first time one of the militants' rockets hit the center of a major Israeli city. The attack also caused no casualties.

The armed wing of Hamas claimed responsibility for the attack. Hamas controls the Palestinian government.

Israel withdrew its troops from Gaza and forced Jewish settlers to leave their homes in the Palestinian territory less than a year ago, after nearly 40 years of occupation.

In the occupied West Bank, Israeli troops killed a Palestinian man during a raid on a refugee camp near Jericho. Palestinian security sources say the man was a member of the al-Aqsa Martyrs' Brigades.

Israeli troops stepped up operations against the Palestinians last month after militants kidnapped an Israeli soldier in a raid.