The conflict over Jerusalem dramatically escalated Monday through Tuesday, resulting in the deaths of at least 24 people - including nine children. Israeli airstrikes and rockets fired by Palestinian militant groups continued late into Monday night and early Tuesday, with explosions heard all over Gaza.

Palestinian health officials said 24 people were killed by Israeli airstikes, including nine chidlren. Israeli officials said there were also civilian dead or injured on its side after several rockets had hit a residnetial building in the city of Ashkelon Tuesday morning. 

Israeli military officials said they carried out airstrikes after Palestinian militant groups fired rockets at some of their positions and on civilian targets in Jerusalem. Israeli officials said Palestinian militants had fired more than 200 rockets, most of which were intercepted by its Iron Dome missile defense systems. Hamas and the smaller Islamic jihad militant group claimed responsibility for the rocket attacks.

"[The] rocket strike against the enemy in the occupied Jerusalem in response to their crimes and aggression against the holy city and its aggression against our people in sheikh Jarrah and Al-Aqsa Mosque," Hamas's armed wing representative, Abu Ubaida, said in a statement.

In retaliation, the Israeli military bombarded several military posts and rocket launchers in Gaza. Israeli Prime Minister Benjamin Netanyahu said the militant groups had crossed the "red line" and fired upon Jerusalem for the first time since 2014.

"Israel will respond very forcefully. We will not tolerate attacks on our territory, our capital, our citizens and our soldiers. Whoever strikes us will pay a heavy price," Netanyahu said.

Israeli military spokesman Lieutenant-Colonel Jonathan Conricus said six rockets were launched toward residential areas in Jerusalem's outskirts. Officials are still trying to confirm casualty reports that are still coming in.

On Tuesday, U.S. Secretary of State Antony Blinken urged both sides to end hostilities. Blinken asked both groups to "immediately" stop firing at each other.

The escalation of violence between the two sides came as Israel celebrated "Jerusalem Day" - an event celebrating its capture of East Jerusalem during the 1967 Arab-Israeli War. Israel considers all of Jerusalem as its capital, including the eastern region that it annexed after the 1967 war against international protests.

Tensions between Israeli security forces and Palestinian protesters have been building up since the Muslim holy month of Ramadan. After learning of the recent attacks, Palestinian President Mahmoud Abbas announced that this year's Eid El-Fitr celebrations - marking the end of Ramadan - will be canceled.