‘My father, 75, died without a will’: His ex-wife, fiancée and children are hiding his financial documents. What can I do?

"My father recently passed away at 75, without a will. At the time, he was divorced from his fifth wife and had a fiancée."

‘My father, 75, died without a will’: His ex-wife, fiancée and children are hiding his financial documents. What can I do?
"My father recently passed away at 75, without a will. At the time, he was divorced from his fifth wife and had a fiancée."