Strong winds blew the bouncy castle several metres into the air during a local fair, authorities said.
Two children have died after strong winds blew a bouncy castle several metres into the air during a fair in eastern Spain.
An eight-year-old girl was declared dead on Wednesday while a four-year-old girl also died of her injuries on Monday.
Seven others were also injured and have since been released from hospital, according to local authorities.
"We deplore the death of the second child, who has been hospitalised in a serious condition since the accident," the Mislata town hall said in a statement on Monday.
The town hall declared an extended period of official mourning and has said all remaining Christmas festivities would be cancelled.
The local fair had been taking place on Tuesday in Mislata, a town that borders the city of Valencia on Spain's eastern coast.
"There are no words, this is a real tragedy," the mayor of the town, Carlos Bielsa, said on Twitter.
Spanish police have opened an investigation to determine whether the bouncy castle complied with safety standards.
Last month, six children died on Australia’s island state of Tasmania after falling from a bouncy castle that was lifted into the air by a gust of wind.