CHICAGO (AP) -- Millionaire adventurer Steve Fossett's wife has asked a court to declare him legally dead, saying she believes he was killed in a September crash of his plane.

Attorney Michael LoVallo filed the petition Monday in Cook County Circuit Court.

LoVallo says that as painful as it is for the Fossett family, it was time to initiate the legal process.

LoVallo says the request was a step toward resolving the legal status of Fossett's estate.

Court papers describe that estate as "vast, surpassing eight figures in liquid assets, various entities and real estate."

The 63-year-old Fossett disappeared on September 3 after taking off in a single-engine plane from an airstrip near Yerington, Nevada. He was heading toward Bishop, California.

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