At least 171 Palestinians and one Israeli soldier have been killed since Israel launched its "Summer Rain" operation against the Palestinian territory on June 28.

The largest Israeli offensive in Gaza since the withdrawal of troops and settlers a year ago was ordered following the June 25 capture of an Israeli soldier by militants.

One of the three groups that nabbed the 19-year-old corporal is the armed wing of the Hamas movement, which shocked Israel and the West when it won Palestinian elections in January and took the helm of government in March.

"The Palestinian government led by Hamas is under constant pressure from the Israeli army," said analyst Nicholas Pelham from the International Crisis Group think-tank.

"The Palestinian Authority simply cannot function because the ministers cannot move in the Palestinian territories" between the Gaza Strip and West Bank.

Israel, which has so far refused an exchange of prisoners, has arrested eight ministers, the parliament speaker and dozens of other Hamas political officials. It also struck several ministries and Prime Minister Ismail Haniya's office.

Israel's wide-ranging assault on the crowded territory has deepened the humanitarian crisis there, with air raids against a power plant and the closure of the Strip leaving the 1.4-million population in dire need of basic supplies.

Since June 28, Israel has also staged several raids and ground operations in the northern Gaza Strip to prevent militants from firing rockets on nearby Israeli towns.

However, militants have continued to fire Qassam rockets -- named after and manufactured by the armed wing of Hamas -- and wounded a dozen Israelis since the end of June.