It was written in the newspaper that the airplane had lost contact.

Literal

Newspaper [in-に] airplane [subject-が] contact [object-を] cut [quotative-と] was-written.

消息を絶つ (しょうそくをたつ) is a set phrase meaning 'to lose all contact, go missing' — literally 'to sever news.' 書いてあった uses ~てある for a resulting state: someone wrote it and the writing remains. に marks the newspaper as the location of the text.