By Alexander Cornwell, Parisa Hafezi and Jeff Mason TEL AVIV/DUBAI/WASHINGTON (Reuters) -Iranian missiles struck Israel's Tel Aviv and the port city of Haifa before dawn on Monday, destroying homes and fuelling concerns among world leaders at this week's G7 meeting that the battle between the two old enemies could lead to a broader regional conflict.

Hundreds of civilians, mostly in Iran, have been killed by dueling airstrikes despite international pleas for de-escalation.

It follows daytime attacks from both sides, with Israeli strikes in Tehran continuing and Iran firing more missiles towards Israel.

The deadly conflict between Israel and Iran has entered a fourth day, with both sides firing waves of missiles overnight. Follow for live updates.

Israel targeted nuclear and military sites in Iran in airstrikes early Friday morning.The strikes are a major escalation that threatens to expand into a wider regional conflict.These are five key questions as the conflict continues.

Israel warns "Tehran will burn" if Iran continues firing missiles, while state media say 60 people have been killed in a strike on Iran's capital.

President Donald Trump has warned Iran the U.S. would retaliate to an attack by Tehran with its "full strength and might" as Israel and Iran launched fresh strikes overnight. On Friday, Israel launched the first of a series of airstrikes across Iran,