An Israeli airstrike in southern Gaza Strip killed two Hamas gunmen during a military operation on Wednesday, the militant group said, the AP reported.
Israeli troops have been operating in the area since Monday to try to halt Palestinian militants from firing rockets into nearby Israeli army bases and communities.
The airstrike also wounded four militants who were firing mortars at Israeli forces, Hamas said. An earlier Israeli hit wounded four militants from Islamic Jihad, a smaller militant group.
The army confirmed both airstrikes, saying it was targeting militants firing mortar shells.
The latest violence undermines faltering Egyptian efforts to mediate a cease-fire between Palestinian militants and Israel in the Gaza Strip. Israel and Hamas have each refused to accept the other's conditions for calm.
Hamas, which rules the Gaza Strip, wants Israel to open commercial border crossings it shares with Gaza. Israel has permitted only a trickle of commercial goods and humanitarian aid to enter the territory since Hamas seized control of Gaza last June. Egypt also has sealed its crossing with Gaza since the Hamas takeover.
Israel, which considers Hamas a terrorist group, has demanded it stop smuggling weapons through tunnels that cross under Gaza and Egypt.