By Jessie Yeung, Adam Renton, Ed Upright, Joshua Berlinger, Aditi Sangal, Dakin Andone, Maureen Chowdhury, Leinz Vales, Elise Hammond, Steve Almasy and Kathleen Magramo, CNN
From CNN's Amir Tal
Israeli Minister of Defense Yoav Gallant says he has given an order for Gaza’s “complete siege.”
No electricity, food, fuel or water will be delivered to the enclave, which is surrounded on three sides by Israel and Egypt.
“We are fighting barbarians and will respond accordingly," he said on camera.
From CNN’s Ibrahim Dahman in Gaza
Hamas says it fired 120 rockets toward the southern Israeli cities of Ashdod and Ashkelon in response to Israeli airstrikes, the militant group said in a statement.
The salvo comes after the group said it fired rockets toward Jerusalem and Tel Aviv further north, setting off sirens in those cities.
From CNN’s Celine Alkhaldi in Tel Aviv
At least 493 people have died and 2,651 have been wounded in Gaza since Israel began carrying out airstrikes in response to Hamas' surprise attack early Saturday morning, the Palestinian health ministry in the enclave said.
From CNN’s Ibrahim Dahman in Gaza, Hadas Gold, Richard Allen Greene, Kareem Khadder and Abeer Salman in Jerusalem, and Celine Alkhaldi in Tel Aviv
Sirens warning of incoming rockets in Jerusalem and Tel Aviv rang out at noon local time (5 a.m. ET) on Monday, the third day of war between Israel and Hamas.
A CNN producer in Gaza saw outgoing rocket fire, and CNN producers in Jerusalem heard booms of what sounded like Israel’s Iron Dome air defense system intercepting incoming rockets.
Hamas later said on social media that it had it fired rockets on Jerusalem and Tel Aviv.
From journalist Lauren Iszo in Tel Aviv
There is no fighting going on between Israel Defense Forces troops and Hamas inside Israel, and the IDF has re-taken control of all communities around the Gaza Strip, IDF spokesman Rear Adm. Daniel Hagari told reporters Monday morning.
The announcement comes more than 48 hours after Hamas launched a surprise attack with thousands of rockets and sent fighters across the border in an incursion the likes of which Israel has not seen since its 1948 War of Independence.
From CNN’s Abeer Salman and Kareem Khadder
Videos and images on social media show mosques and residential buildings flattened in Gaza, as the death toll in the territory rose to at least 436 people on Monday.
The Israel Defense Forces (IDF) said Monday it attacked 500 Hamas and Palestinian Islamic Jihad targets overnight.
The Palestinian interior ministry said most of the targets were “towers, residential buildings, civil and service facilities, and many mosques.”
Mosques and homes hit: The IDF claimed Monday that two Hamas operational assets were struck inside a mosque in Gaza. It claimed to have struck another seven Hamas command centers, an Islamic Jihad command center, and numerous multi-story buildings including the home of Hamas secretary Ruhi Mashtaa.
Hamas denied that the buildings targeted were used by the militant group, saying residential homes were targeted without warning.
Thousands displaced: The United Nations Relief and Works Agency (UNRWA) said nearly 74,000 people in Gaza were displaced and taking shelter in their schools. Those numbers are "likely to increase as heavy shelling and airstrikes continue including on civilian areas," it said.
The agency said one UNRWA school sheltering people was directly hit.
From CNN’s Benjamin Brown
Germany "has to assume" there are German citizens among those captured by Islamist militant group Hamas on Saturday, a German foreign office source told CNN Sunday.
“As far as we know, they are all people who have Israeli citizenship in addition to German citizenship,” the source said.
The German foreign ministry and German embassy in Tel Aviv are coordinating “very closely” with Israeli authorities, the source said.
The source added that Germany will not comment publicly on the number of kidnapped or individual cases to protect those individuals.
CNN earlier confirmed the identity of German-Israeli woman Shani Louk, who was seen unconscious in a video in the custody of armed militants in Gaza. Her mother told CNN she discovered Louk had been captured at a music festival near the Gaza border through a viral video on social media.
Hamas has claimed it is holding more than 100 hostages.
From CNN's Yong Xiong
An Israeli father is missing after he rushed to a music festival near the Gaza-Israel border to save his daughter during an attack by Hamas militants, his family told CNN on Sunday.
Mark Peretz was on the phone with his daughter Maya, who was at the outdoor Nova Festival event Saturday, when he heard gunshots and screaming.
“When we started to figure out that Hamas just crossed the borders ... my father understood that my sister’s gonna be kidnapped soon, so he decided to take the car and started to drive south,” said Peretz’s son Gilad Peretz.
Gilad said his father reached the site of the festival around 8:30 a.m.
When he called, "I heard shots and he tried to say 'don't shoot them,'” Gilad said. He lost contact with his father soon after.
“He might be kidnapped or dead at this moment,” Gilad said.
His sister Maya managed to escape Hamas militants by running and hiding in bushes and trash cans, and later took shelter in a police station, Gilad said. She made it home safely.
“My father is a fighter. He is a family guy, and he just tried to go save his daughter. Life will go on. I (have) hope with him. We miss him,” Peretz said.
Israeli rescue workers later said they found at least 260 bodies at the festival site. Some attendees were taken hostage, seen in social media videos being seized by their armed captors.
From CNN’s Richard Allen Greene and Sophie Jeong
The community of Be'eri in southern Israel was "very badly hit" during an attack by Islamist militant group Hamas, an Israel Defense Forces (IDF) spokesperson said Monday.
"We thought we would need more rooms [to house the evacuees]. We didn't need all the rooms,” Lt. Col. Richard Hecht said during a briefing.
Israeli troops are still fighting in the kibbutz, though most Hamas militants there have been killed, Hecht added.
Be'eri lies just three miles (5 kilometers) from Gaza's eastern border.
Videos obtained and geolocated by CNN show that at least four civilians were killed while in Hamas custody, just feet from where armed militants had been escorting them in Be'eri.
