Chris Hemsworth and Elsa Pataky -- Give Birth to Twins

Chris Hemsworth and his wife are at Cedars Sinai Medical Center right now giving birth to twins ... TMZ has learned.

It's ultra-high security in their hospital suite ... we're told 2 security guards are standing at the door. Chris is strolling the hallway and is being escorted with a guard.

Chris and his wife Elsa Pataky already have one baby -- India Rose Hemsworth who is now 22 months old. She's about to have a couple new siblings.