Commenting on the heavy fighting underway in Gaza, IDF Chief of Staff Lt.-Gen. Benny Gantz said Sunday the army sustained high casualties over the past 24 hours.Soldiers took part in "difficult and complex battles, but we are determined to complete the mission," Gantz added. "I'm proud of the work that our boys are doing."Addressing civilian casualties in the central Gazan area of Shejaiya, Gantz said Palestinian residents know they have "fallen victim to Hamas's [war] preparations in their area. I'm very sorry for civilians that have been harmed. It hurts me to see women and children who have been hit. There is no other state in the world that sets up a field hospital, during combat, on behalf of the side it is fighting." "We have a moral obligation to avoid civilian casualties. We also have a moral obligation to defend our people," Gantz said. Ground forces are making gains and are seizing target areas, the chief of staff stated, adding that Hamas was sustaining blows "every hour." The IDF will not be deterred by the difficult combat it saw over the past 24 hours, Gantz said. While the conflict should be kept as short as possible, Israel's targets in improving security for its civilians must be met, the chief of staff added.