Iran has launched a new wave of missile attacks on Israel, triggering air raid sirens across the country as emergency services reported projectiles striking and shrapnel falling in Israel's north and center,

Israel and Iran kept up their attacks, killing and wounding civilians and raising concern among world leaders meeting in Canada this week that the biggest battle between the two old enemies could lead to a broader regional conflict.

Dozens of others were injured overnight across Israel, the authorities said. Israel was striking military sites in Iran and the four-day-old conflict showed no sign of slowing.

Onlookers gathered on Saturday at a central Tel Aviv residential building next door to Israel’s defense headquarters that was damaged after it took a hit from what appeared to be shrapnel from an overnight missile barrage from Iran.

Israeli citizens were ordered to head to bomb shelters on Friday night amid retaliatory missile strikes from Iran.

Delta Air Lines Inc. and United Airlines Holdings Inc. suspended flights to Tel Aviv following Israel’s bombing of Iran and the closure of Israel’s airspace.