JERUSALEM  As the Gaza death toll passed an estimated 1,000 people and concerns about the humanitarian situation inside Gaza grew, Egypt announced on Wednesday that it was making progress toward an interim cease-fire, with some officials predicting that one could be five to six days away.

The Israeli military operation continued apace in southern Gaza with the military reporting that its warplanes carried out three dozen bombing raids. Still, with the cease-fire talks edging forward and Israeli leaders concerned about sending their troops into the heart of Gaza City, Israel held off on expanding its war to the next phase.

Hamas’s militants fired more than a dozen rockets into Israel, including four longer-range ones that landed near the cities of Beersheba and Ashdod, sending a message of menace but causing no injuries. Three rockets were also fired from Lebanon into northern Israel, and Israel returned fire to the source.

Also on Wednesday, nine Israeli human rights groups called for an investigation into whether Israeli officials had committed war crimes in Gaza. The groups say that tens of thousands of civilians in Gaza have nowhere to flee, the Gaza health system has collapsed, many people are without electricity and running water, and some are beyond the reach of rescue teams.