Iran’s aviation body on Sunday announced the cancellation of flights at some of the country’s airports, citing “operational restrictions”, state media reported as Israel vows to retaliate for an Iranian missile strike.

Because of those restrictions, “the flights at some airports of the country will be cancelled from 21:00 tonight (1730 GMT), Sunday, October 6, until 6:00 am tomorrow, October 7,” according to IRNA state news agency citing Iran’s Civil Aviation Organisation spokesman, Jafar Yazarloo.

Iran on Tuesday launched around 200 missiles in its second direct attack on Israel, in what it said was retaliation for the killing of Tehran-aligned militant leaders in the region, along with a general in Iran’s Revolutionary Guards.

Ever since, Israel has said that it will respond to Iran’s attack.

On Tuesday night, Iran closed its airspace for less than two days until Thursday morning.

The aviation body announced then that both domestic and international flights were grounded for security reasons until the reopening.

The European Union Aviation Safety Agency has advised European airlines to avoid Iranian airspace until October 31, with the situation under ongoing review.