Iran fired a new wave of missile attacks on Israel early Monday, triggering air raid sirens across the country as emergency services reported at least five killed and dozens more wounded in the fourth day of a conflict between the regional foes that showed no sign of slowing.

Israeli forces stepped up bombing of Iranian cities, while Iran pierced Israeli air defences with a successful volleys of retaliatory missile strikes.

Aerial attacks between Israel and Iran continued overnight into Monday, marking a fourth day of strikes following Israel's Friday attack. That surprise strike hit the heart of Iran's nuclear program, killing several nuclear scientists as well as high-ranking military leaders, according to Israeli officials.

Iran has launched a new wave of missile attacks on Israel, triggering air raid sirens across the country as emergency services reported at least five killed and dozens more wounded in the fourth day of open warfare between the regional foes.

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.

Video verified by CNN captures the dramatic moment a missile struck in vicinity of the Kirya, an area of Tel Aviv that’s home to an urban military base housing Israel’s Defense Forces.

Residents awoke to mostly quiet streets in Tel Aviv after spending the night running back and forth to bomb shelters after Iran’s attacks on the coastal city. Some restaurants and cafes were closed, although those that remained open were full of people drinking coffee and eating pastries as normal.