Israel blamed the attack on Hamas, which it said had allowed "violent riots" along the security fence separating Gaza from Israel, and then launched rocket attacks on Israeli communities. IDF fighter jets, attack helicopters and other aircraft hit what it described as drones and munitions plants and training grounds.
The IDF had previously announced that it was "operating in the Gaza Strip," and "explosions heard" in this area were directly related to the IDF's operations.
"The IDF is currently operating in Gaza Strip. The explosions heard are related to this activity."
Palestinian media reported before the IDF announcement that Gaza was under attack.
According to Israeli news site Haaretz, the Israeli Air Force conducted 30 strikes, though it's unclear if this referred to the number of IAF aircraft in the operation, the number of projectiles fired, or the number of targets attacked.
Rocket sirens have started alerting residents of potential rocket fire after the IDF announced it was undertaking a military operation.
A Snapchat video shows people laughing and joking around near a soccer field before a rocket lands nearby. "Those guys should have been [in] a bomb shelter," said Anna Aronheim, a Jerusalem Post reporter and security consultant.
Israeli reporters have shared footage of what they say is the Iron Dome defense system shooting down incoming mortar and rocket fire.