Explosions are rocking an ammunition depot in Russia, and a news agency quotes a regional governor as saying 35 people are missing.

Television networks are broadcasting footage showing intermittent explosions sending flames and thick smoke into the sky over the military facility in the Ulyanovsk province, a few hundred miles east of Moscow.

The provincial government says the blasts and fire have persisted hours after first erupting while ammunition was being destroyed at the arsenal.

The Interfax news agency quotes regional governor Sergei Morozov as saying 35 workers are missing, 10 people have been hospitalized and some 3,000 civilians have been evacuated from the area.