A combined attack of dozens of ballistic missiles and hundreds of drones from Iran triggered air raid alerts across Israel early on Sunday, the Israeli army said, as residents reported multiple bombings were heard.

The projectiles triggered sirens in Jerusalem, the Negev Desert and the Dead Sea in the south, the Israeli-annexed Golan Heights in the north as well as the occupied West Bank.

Israel Defense Forces (IDF) Spokesman Daniel Hagari confirmed on Saturday during a press briefing that Israel was under attack by ballistic missiles and unmanned aerial vehicles from Iran, noting that aerial defence systems have intercepted some of the missiles.

Israel’s state-owned Kan TV news reported that about 100 drones, out of about 400-500 that have been launched, were intercepted before reaching Israel by allied countries, including the US, Jordanian and British forces.

Israel’s Maged David Adom rescue service said in a statement that a 10-year-old boy from a Beduin village in the Negev was seriously injured. A projectile or parts of a projectile fell near Umm Al Fahm, an Arab city in northern Israel, causing no injuries.

Israel is planning to launch a “significant response” to the Iranian aerial attack, Israel’s state-owned Kan TV news reported early on Sunday, citing an anonymous senior Israeli official.

“The fact that Iran fires for the first time from its territory at Israel requires a significant response. It will come soon,” the official said.

Iran’s Islamic Revolutionary Guards Corps (IRGC) confirmed in a broadcast statement on Saturday night that it had launched missile and drone attacks on Israel.

Israel’s state-owned Kan TV news reported that the drones were launched from Iran as well as from other countries allied with Iran.

The Israeli military said earlier in a statement that “the IDF Aerial Defense Array is on high alert, along with Israel Air Force fighter jets and Israeli Navy vessels that are on a defence mission in Israeli air and naval space”.

Meanwhile, two Israeli officials, speaking on condition of anonymity, confirmed to Xinhua news agency that several cruise missiles were also launched from Iran toward Israel.

Israel has been on heightened alert over the past few days following Iranian threats to avenge the killing of seven Iranian officers in its consular building in Damascus, Syria, earlier in April, which was carried out by Israel, according to Iran.