WARSAW, Poland (AP) — Officials say that seven people have been killed by toxic fumes after entering a septic tank in Poland. Four of the victims belonged to one family.

Police spokeswoman Sylwia Wroniec said the accident Thursday occurred after a man entered the tank to clean it and apparently lost consciousness. Seven more people entered to rescue him and all succumbed to the toxic gases except for one woman. She was taken by helicopter to a hospital and is fighting for her life.

Prosecutor Zbigniew Fafera said the victims include a father, his two sons and a daughter-in-law.

The accident occurred in Karczowka, a village in western Poland.

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