The warning came on the fourth day of the conflict, when the Israeli military claimed it had achieved air superiority over the Iranian capital and could fly over the city without facing major threats.

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 Israel Defense Forces said alerts were activated in several areas of the country after the detection of missiles launched from Iran toward Israel. The Air Force was working to intercept them, the IDF said.

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