where in the novel does Hawthrone tell us that Hibbins later is executed for witchcraft?

From the Text:

"As they descended the steps, it is averred that the lattice of a chamber-window was thrown open, and forth into the sunny day was thrust the face of Mistress Hibbins, Governor Bellingham’s bitter-tempered sister, and the same who, a few years later, was executed as a witch."

(Chapter 8)