It's not in the Bible, that is correct, but it is historical fact.
Other historical facts that have been brought to us from that time period include the books of Josephus. You can read about the destruction of the Temple by the Romans from him, and it is an horrific account. It is, in all likelihood, what Jesus spoke of when he talked about the Kingdom of God coming within this generation.
A vast number of Jews were killed by Titus leading the Roman army.