The Israeli military alleges that the rocket, with 120 km reach, was fired from the Gaza strip. It accused Hamas, the party who rules the Gaza strip, of launching the rocket. Hamas denied that it was involved.
How Israel's prime minister Bibi Netanyahoo reacts to the attack will decide about his fate in the April 9 general election.
The Israeli military deployed an infantry and an army brigade towards the Gaza strip and called up thousands of reservists.
Netanyahoo met Trump in the White House today and is now flying back to Israel. His planned speech before the Zionist lobby AIPAC was canceled as were his meetings with Congress leaders.
Netanyahoo's political competition is pushing him towards a wider escalation: