A fire has broken out at a natural gas terminal in the Russian Baltic Sea port of Ust-Luga, the regional governor said early Sunday.

The terminal, 110 kilometers (70 miles) west of St Petersburg near the Estonian border, is operated by Novatek, Russia's largest independent natural gas producer.

"No casualties as a result of a fire at Novatek's terminal in the port of Ust-Luga. Personnel were evacuated," Aleksandr Drozdenko, governor of Leningrad Oblast, posted on Telegram along with a short video showing a massive fire and smoke at a chemical complex.

"A high alert regime has been introduced in the Kingiseppsky district (which includes the port)," he said.

The Russian ministry of emergency situations and local fire service were involved in fighting the blaze, he added.

TASS news agency and other state media said the cause of the fire has not been announced.

The Ust-Luga complex processes natural gas condensate into naphtha, jet fuel and ship fuel components, according to Novatek's website.