JERUSALEM (Reuters) -- Israel's aerial assault on the Gaza Strip on Wednesday could draw cross-border Palestinian rocket attacks and stretch into days of fighting, the Israeli military spokesman said.

"The days we face in the south will, in my estimation, prove protracted," Brigadier-General Yoav Mordechai told Channel 2 TV after Israeli air strikes killed the military chief of Gaza's Hamas government.

"The homefront must brace itself resiliently."