DUBAI, United Arab Emirates (AP) — Commercial flights began diverting their routes early Friday morning over western Iran without explanation as one semiofficial news agency in the Islamic Republic claimed there had been “explosions” heard over the city of Isfahan. State television acknowledged “loud noise.”

The incident comes as tensions remain high in the wider Middle East after Iran’s unprecedented missile-and-drone attack on Israel.

Dubai-based carriers Emirates and FlyDubai began diverting around western Iran about 4:30 a.m. local time. They offered no explanation, though local warnings to aviators suggested the airspace may have been closed.

The semiofficial Fars news agency reported on the sound of explosions over Isfahan near its international airport. It offered no explanation. However, Isfahan is home to a major airbase for the Iranian military, as well as sites associated with its nuclear program.

Iranian state television began a scrolling, on-screen alert acknowledging a “loud noise” near Isfahan, without immediately elaborating.