PRAGUE (AFP) - A fire at a high-rise apartment block in the Czech Republic killed 11 people, including three children and five other people who jumped to their deaths, firefighters said.

The fire occurred in the eastern Czech Republic near the Polish border.

"The fire broke out in a flat on the 11th floor," Lukas Popp, a spokesman for local firefighters, told AFP.

"Six people died on this floor, including three children and three adults - and a dog," he added.

"Our firefighters were on the site really fast but during the action, five people jumped out of the 12th-storey window and died," said Popp.

Police originally reported ten dead in the fire in a 13-storey concrete block of flats in the city of Bohumin on the Czech-Polish border some 300km east of the capital Prague.

"The fire has been localised, we are now moving our units away," said Popp, adding investigators were looking into the causes of the deadly blaze.

Czech Interior Minister Jan Hamacek said in a tweet a firefighter had suffered a serious injury in the fire which he described as "a huge tragedy".

"My deepest condolences to the bereaved," he said, adding: "I wish a speedy recovery to the injured firefighter."