STORY: Israel vowed to escalate its response to an attack by the Palestinian militant group Hamas with a ground offensive, while U.S. President Joe Biden pledged support for Israel and issued a warning to anyone who might seek to take advantage of the situation.Israel said dozens of its fighter jets struck more than 200 targets overnight on Wednesday in a neighborhood of Gaza City that it said had been used by Hamas to launch its unprecedented wave of attacks.Gaza's health ministry said at least 950 people have been killed and 5,000 injured in the crowded coastal enclave.On Saturday, Hamas gunmen from the Gaza Strip rampaged through parts of southern Israel, in the deadliest Palestinian militant attack in Israel's history.Israel's military said the death toll in Israel had reached 1,200 and more than 2,700 people had been wounded.