The Israeli air force reentered Gaza on Saturday night and attacked a building used as a Hamas base in the northern Gaza Strip. Palestinian sources said two were killed and six wounded. Another three Palestinians were reported killed and 11 wounded in air force strikes in Beit Hanoun on Sunday. As troops rolled through Beit Hanoun Palestinian terrorists exchanged fire with Israeli soldiers and set off a land mine near an Israeli army bulldozer. Palestinian witnesses said Israeli tanks and bulldozers rolled across the Gaza-Israel border as part of a new land operation.