The advisor to the Mariupol mayor Petro Andriushchenko said this on Telegram, Ukrinform reports.
"There was a strong blast in the area of Azovstal. Air defense was also recorded," Andriushchenko said, adding that details would follow later.
As reported, explosions have recently become more frequent in the captured Mariupol. The invaders are turning the city and surrounding villages into a military and logistics hub. In particular, Russians have set up warehouses and are repairing military equipment on the territory of the Azovstal steel plant.