Israel faced a missile attack on Sunday as Iran said it reserved all options to defend itself after unprecedented US strikes that President Donald Trump said had "obliterated" its key nuclear facilities.

Hours after Trump dramatically escalated Middle East tensions by sending B-2 bombers to Iran, the Israeli military warned people to seek cover from a barrage that appeared heavier than the Iranian salvoes fired in the past few days.

Three areas of Israel including coastal hub Tel Aviv were hit on Sunday morning by waves of Iranian missile attacks, with at least 23 people injured, according to rescue services and police.

Several buildings were heavily damaged in the Ramat Aviv area in Tel Aviv, with holes torn in the facades of apartment blocks.

"Houses here were hit very, very badly," Tel Aviv mayor Ron Huldai told reporters at the scene.

"Fortunately, one of them was slated for demolition and reconstruction, so there were no residents inside.

"Those who were in the shelter are all safe and well. The damage is very, very extensive, but in terms of human life, we are okay."

The Israeli police said in a statement that they had been deployed to at least two other impact sites, one in Haifa in the north and another in Ness Ziona, south of Tel Aviv.

Eli Bin, the head of Israeli rescue service Magen David Adom, told reporters that a total of 23 people had been wounded nationwide in the attacks.

Sirens rang across the country, with air defences activated shortly afterwards, causing loud explosions heard in Tel Aviv and Jerusalem. (Agencies)