Israel ? Palestinian militants from the Gaza Strip crossed into Israel and killed two civilians at a vital fuel depot Wednesday. The surprise attack prompted an immediate Israeli military push into Gaza that threatened to spiral into wider clashes.

At least 20 Israeli tanks rushed into northern Gaza in the wake of the mid-afternoon attacks at the Nahal Oz terminal, currently the only conduit for gasoline shipped into the coastal strip. Subsequent Israeli shelling and airstrikes killed at least nine Palestinians, officials in Gaza said.

The radical Palestinian faction Islamic Jihad, along with Mujahedin Brigades and the Popular Resistance Committees, claimed responsibility for the attack. Hamas, the militant group that controls Gaza, did not claim a role, but Hamas spokesman Fawzi Barhoum later praised the attacks as “heroic.”