Some 8,000 pigs died in a blaze at a factory farm in Heusden in the province of Brabant on Tuesday, taking the total number of animals to die in farm fires this year to over 100,000.

The Brabants Dagblad reported that one of the farm workers heard an explosion shortly before the fire ripped through two barns housing the pigs.

Heusden is the latest in a series of fires to hit factory farms in the Netherlands. In August some 2,500 pigs died in Didam near Arnhem while a year ago 20,000 pigs died at a mega farm in Gelderland.

According to animal welfare organisation Wakker Dier some 100,000 animals have died in fires so far this year. Last year, there were 47 factory farm fires in the Netherlands and 229,000 animals were killed.

An action plan to cut the number of fires put together by the industry, plus animal protection group Dierenbescherming, insurers and the fire brigade, says more needs to be done to make old barns more fire proof.

Checks of the electrical installations of all barns housing livestock, one of the measures proposed in the plan, are currently under way. Thousands of barns have already been looked at.

However, the plan does not include compulsory lightning conductors and sprinkler systems, stating instead that more research needs to be carried out.

Last July, the pro-animal PvdD introduced a motion to parliament calling for better fire safety at factory farms, but it failed to win enough support. The three Christian parties and two Liberal parties D66 and VVD voted against the measure.