U.S. Treasury yields fell on Friday, amid a global flight to safety in the wake of Israeli airstrikes on Iran.

The yield on the benchmark 10-year Treasury moved 2 basis points lower to 4.334% at 3:02 a.m. ET. Yields on 2- and 5-year notes were around 2 basis points lower, while long-dated Treasurys also cooled.

One basis point equals 0.01%. Bond yields and prices move in opposite directions.

The moves come after Israel launched a series of airstrikes on Iranian soil, saying sites linked to Iran’s nuclear program had been targeted. The attack killed Mohammad Hossein Bagheri, head of the Iranian Armed Forces, as well as Hossein Salami, chief of Iran’s Islamic Revolutionary Guard Corps, according to Iranian state media.

Two of Iran’s top nuclear scientists were also reportedly killed in the airstrikes.