T-Rex Attack: War In The Time Stream - The T-Rex Attack Series, #1

In addition to the dinosaur attacks, the Russians have set up a base in 1248 A. D., Arizona, where they are using captured Apache slaves to grow opium. The plan is to flood the streets of America with cheap heroin, and create an avalanche of new drug addicts. Not to be out done, the United States sends its own team from the newly created Time Travel Service to counter the enemies' efforts. They intend to do this by catching their dinosaurs for a revenge attack against Russian targets.
The Americans also have the goals of destroying the enemies' bases, and ending their ability to ever attack the U. S.