Hamas has vowed revenge on Israel after seven of its members were killed in an air strike in the deadliest exchange of fire since the latest round of attacks began weeks ago. Hamas, which rules the Gaza Strip, said "the enemy will pay a tremendous price", referring to Israel.
The group said its men were killed by an Israeli air strike early on Monday morning on a tunnel used by the militants.
Two militants from a different group were also killed in a separate strike. The men were involved in rocket attacks on southern Israeli communities, the Israeli military said.
Israel said it carried out air strikes on at least "14 terror sites" including "concealed rocket launchers" in Gaza overnight in retaliation for a recent spike in attacks from Gaza.