Israeli raids into northern Gaza Strip today killed six Hamas gunmen and a schoolteacher.
Residents said tanks and heavy bulldozers penetrated the border fence near the town of Jabalya in the coastal territory.
Israeli forces also struck in Beit Hanoun, a border community often used by Palestinian militants to fire rockets into Israel.
Hamas said five of its gunmen died fighting the Israeli troops. Another gunman, from Islamic Jihad, also died in the clashes, it said.
Hospital officials said an Israeli missile hit a school in Beit Hanoun, killing a teacher and wounding two colleagues.
Hamas said it was responsible for a Palestinian suicide bombing that killed a woman in Israel on Monday, the first such claim from the group since 2004.
Israeli forces frequently carry out raids in Gaza to try and counter cross-border rocket fire by Hamas and other militant groups.
Hamas seized control of the Gaza Strip in June when it routed secular Fatah forces loyal to Palestinian President Mahmoud Abbas, who has revived peace talks with Israel.