Mormon 3:4

And it came to pass that after this tenth year had passed away, making, in the whole, three hundred and sixty years from the coming of Christ, the king of the Lamanites sent an epistle unto me, which gave unto me to know that they were preparing to come again to battle against us.

From section: Two Lamanite Attacks at Desolation

From page: Nephite Decline and Downfall