How Israel's Iran attack could open 'Pandora's box' for the Middle East — and the U.S.

Iran was left with no choice but to retaliate against Israel’s sweeping strikes on its nuclear facilities and targeted killings of senior officials, experts of the region said.

Iran had no choice but to retaliate against Israel’s sweeping strikes on its nuclear facilities and targeted killings of senior officials, experts of the region said Friday, risking an escalation that could drag the United States into a spiraling conflict.

Late on Friday, loud blasts were heard throughout Israel and the public was told to take shelter after the military said it identified missiles being launched from Iran. Iran launched “hundreds of ballistic missiles," Iran’s Islamic Republic News Agency reported, adding that “the hard retaliation has begun.”

While not a surprise, Israel's earlier attack was remarkable in its severity, with some 200 Israeli fighter jets hitting one of Iran’s main uranium enrichment sites; striking the capital, Tehran; and killing many top military leaders. Israeli Prime Minister Benjamin Netanyahu has vowed more was to come.

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This left the Islamic Republic with few options, having been weakened by a succession of Israeli strikes over the past year, experts warn.