jerusalem -- An Israeli airstrike killed four Palestinian militants in the Gaza Strip and a rocket exploded near a home Sunday in southern Israel, continuing a surge of fighting that has threatened to unravel a 5-month-old cease-fire.
Israeli Prime Minister Ehud Olmert told a weekly Cabinet meeting that he had asked his security chiefs to present proposals for military action if necessary to halt rocket fire from the Gaza Strip.
In Gaza, a spokesman for the Popular Resistance Committees, whose members were killed in the airstrike, warned that Israel would "bear the consequences and responsibility" for what he called its decision to end the cease-fire.
The group is allied with Gaza's Hamas rulers.
Violence across the border broke out Nov. 4, when Israeli forces crossed into the Gaza Strip to destroy what the army said was a tunnel dug by Hamas in a plan to seize an Israeli soldier. Six gunmen were killed in the raid, and militants responded with volleys of mortar shells and rockets into Israel.