The Israeli military claims it has found a Hamas command post and weapons at Al-Shifa Hospital in the Gaza Strip.
The military said on Wednesday that troops raided the largest hospital in the enclave, where it says Hamas has a key base. The military said it is continuing a "precise and targeted operation."
It said ground forces killed many Hamas fighters in the compound.
In a video released by the military, a spokesperson said guns and other weapons were hidden behind medical equipment.
Hamas says the hospital is dedicated to medical care and citizens and not a military facility. It said on Wednesday on social media that Israel's claim is lies and propaganda that it uses to justify its crimes.
Israeli Prime Minister Benjamin Netanyahu has stressed his country will continue the operation. He said at a military base near Gaza on Wednesday that there is no place that Hamas militants can hide, and that the military will eliminate Hamas and bring back the hostages it took.
Al Jazeera quoted Gaza health authorities as saying there are about 2,500 people in the hospital, including patients, newborns, medical staff and evacuees.
Palestinian health minister Mai Alkaila said in a statement on Wednesday that there is a risk of a massacre at the hospital.