Israel pounded Hamas targets with airstrikes today, killing six people and wounding dozens as it stepped into intense fighting between the Islamic militants and the rival Fatah movement of Palestinian President Mahmoud Abbas.
The Israeli attacks followed Hamas rocket barrages on southern Israel. The strikes made it harder for Hamas gunmen to move around, and prompted accusations - on Hamas websites, radio and TV - that Abbas-linked forces are in cahoots with Israel.
Hamas contemptuously called Fatah fighters the "Army of Lahad", a reference to a Lebanese general allied with Israel in the past.
Israel unleashed the air campaign - a hit on a Hamas command centre, on a trailer housing bodyguards and two vehicles - after Gaza militants fired more than 50 rockets on the Israeli border town of Sderot in three days.
US State Department spokesman Sean McCormack said Israel showed "great restraint".
The airstrikes came on the fifth day of internal violence that appeared to be crushing the Hamas-Fatah unity government, formed just two months ago, along with any hope of renewed peacemaking with Israel.
In all, 45 Palestinians have been killed in the infighting since Sunday, including three today, in the worst round in more than a year.