Smoke and missiles have lit up the skies in Israel and Iran in a fierce standoff triggered by fears over Tehran’s expanding nuclear program. Since June 13, hundreds of military strikes have been exchanged as the two nations remain locked in a conflict that shows no signs of abating.

The two powers have been exchanging barrages since Israel attacked Iran and killed many of the country’s top military leaders and scientists.

The Iran regime is very weak,” Israeli Prime Minister Benjamin Netanyahu said in a television interview. Israeli struck energy facilities and government buildings Sunday.

Although Iran maintains that its nuclear program is for peaceful energy purposes, Israel has long seen it as a threat. Israeli strikes have hit three of Iran’s nuclear facilities — Natanz, Isfahan and Fordow. Little damage appears visible in satellite imagery of Fordow.

The retaliatory strikes came on Saturday, a day after Israel killed top Iranian military leaders and scientists and destroyed an aboveground nuclear enrichment plant near Natanz.

Israel and Iran have begun a new round of attacks, as the conflict between the two heavily armed rivals enters its fourth day.

Israeli strikes have killed at least four senior Islamic Revolutionary Guard Corps commanders, including Hossein Salami.

CBS News New York's Dick Brennan has the latest on the conflict and what President Trump said Monday.