Defense Minister Ehud Barak, signaling stronger Israeli military action against Palestinian militants, said on Thursday they would be made to pay a price for firing rockets toward Tel Aviv.
He also announced he had ordered the military to enlist more reservists "so that we can prepare for any development". The Israeli armed forces chief spokesman said the military had the green light to call in up to 30,000 reserve troops.
In remarks broadcast after rockets were fired at Tel Aviv, Barak said: "This escalation will exact a price that the other side will have to pay."
An Israeli security source said one rocket, which triggered air raid sirens in Tel Aviv, landed in the sea. The military said another rocket fired at central Israel struck an uninhabited area in the Tel Aviv suburb of Rishon Lezion.
Writing by Jeffrey Heller, Editing by Crispian Balmer