Israeli tanks and troops entered the southern Gaza Strip and planes attacked three bridges and a power station, knocking out electricity in most of Gaza early Wednesday, following the abduction of an Israeli soldier by Palestinian militants on Sunday.

The Israeli army has confirmed the start of the major offensive code-named "Summer Rain," adding that the military operation aimed to secure the return of the kidnapped soldier.

Much of the northern Gaza Strip sank into darkness after Israeli war planes bombed power station, three bridges in a series of night-time raids.

The night sky was lit up by flames from the power station in central Gaza and loud blasts were heard in the southern city of Rafah as combat helicopters hovered above.

Israeli tanks and soldiers began taking up positions in two locations of east of Rafah under the cover of tank shells, as Palestinians dug in behind walls and sand embankments in preparation for an Israeli offensive, witnesses and army officials said.

It is the first major ground offensive by the Israeli army since Israel withdrew troops and soldiers from the entire Gaza Strip last summer after 38 years of occupation.

The Israeli strikes came amid intensive diplomatic efforts in the Arab world and by the United Nations to defuse mounting tensions between Israelis and Palestinians.

Just moments ago, Palestinian security forces said that the Israeli army demanded Palestinian security forces withdraw from the key Rafah crossing on the southern Gaza border.

The 19-year-old Israeli Corporal Gilad Shalit was seized by Palestinian militants who mounted a deadly attack on an Israeli army post near the Gaza border on Sunday.

Israeli Prime Minister Ehud Olmert has turned down demands by the Palestinian militants to set free Palestinian women and minors jailed by Israel in exchange for information about the abducted soldier.

Two other Israeli soldiers were killed and four wounded in the predawn Sunday attack. Two Palestinian militants were also shot dead in the gunbattle with Israeli forces. Israel has vowed retaliation for the cross-border assault.

To defuse the rising tensions, negotiators from the Hamas government said Tuesday they had accepted a document implicitly recognizing Israel. But Israel said only the freedom for the captured soldier could defuse the crisis.

In a new development, the Hamas-linked Popular Resistance Committees (PRC), one of the three groups that carried out Sunday's attacks, said it had also kidnapped a Jewish settler in the West Bank.

After Israel launched its Gaza assault, the PRC threatened to kill its hostage Shalit.

Source: Xinhua