Israel and Iran kept up their attacks, killing and wounding civilians and raising concern among world leaders meeting in Canada this week that the biggest battle between the two old enemies could lead to a broader regional conflict.

President Trump rejected an Israeli plan in recent days to kill Iran's Supreme Leader Ayatollah Ali Khamenei, a senior U.S. official told USA TODAY.

President Donald Trump said Sunday that the U.S. is not involved in Israel's military strikes, but "it's possible we could get involved."