DUBAI, United Arab Emirates (AP) — Intense Israeli airstrikes targeted Iran’s capital early Wednesday after it issued a warning about a new area it could target, a day after U.S. President Donald Trump demanded “unconditional surrender.”

Uncertainty roiled the region and residents of Tehran fled their homes in droves on the sixth day of Israel’s air campaign aimed at Iran’s military and nuclear program.

As the U.S. sent warplanes to the Middle East, Trump warned Supreme Leader Ayatollah Ali Khamenei that the U.S. knows where he is hiding and called for Iran’s “UNCONDITIONAL SURRENDER” in a post online, without elaborating.

Trump posted that there were no plans to kill Khamenei “at least not for now.”

The U.N. nuclear watchdog also said for the first time that Israeli strikes on Iran’s main uranium-enrichment facility at Natanz had damaged its main underground centrifuge facility, not just an above-ground facility.