Spanish pop star Joana Sainz García has died after an exploding firework struck her during a concert, international media report.

According to El Diario Montañés, the 30-year-old singer was performing with the Super Hollywood Orchestra when she was hit by a cartridge from a pyrotechnic device and was knocked unconscious.

She was taken to a hospital where she was later pronounced dead.

The accident happened on the closing night of a four-day festival.