JERUSALEM » Israel’s military said Thursday it was calling up another 16,000 reserves, a move that allows it to substantially widen its 23-day campaign against Islamic militants in the Gaza Strip.

The new call-up orders follow another day of intensive fighting, in which 116 Palestinians and three Israeli soldiers were killed.

It also coincides with stalled diplomatic efforts to end the war, which has already claimed more than 1,360 Palestinian lives — most of them civilians — and reduced entire Gaza neighborhoods to rubble.

Fifty-six Israeli soldiers and three civilians on the Israeli side have died in the campaign, as Palestinians have fired hundreds of rockets at Israel — some reaching major cities — and carried out attacks inside Israel through tunnels beneath the heavily guarded frontier.

Israel has now called up a total of 86,000 reserves during the Gaza conflict, which it launched on July 8 to try to end rocket fire from Hamas and other militant groups in Gaza.

An initial aerial campaign was widened into a ground offensive on July 17. Since then the campaign has concentrated on destroying more than 30 cross-border tunnels that militants have constructed to carry out attacks on Israeli territory.

Israel says that most of the 32 tunnels it has uncovered have now been demolished and that getting rid of the remainder will take no more than a few days.

Wednesday marked a second day of particularly heavy Israeli air and artillery attacks, at a time when Egyptian cease-fire efforts appeared to have stalled. Israeli media said late Wednesday that Israel’s Security Cabinet decided to press forward with the operation.

Egyptian officials, meanwhile, met with an Israeli envoy about Israel’s conditions for a cease-fire, including disarming Hamas, according to a high-ranking Egyptian security official, who spoke on condition of anonymity because he was not allowed to discuss the delicate diplomatic efforts.

Hamas has said it will only halt fire once it receives guarantees that a seven-year-old Gaza border blockade by Israel and Egypt will be lifted.