WATCH: Chiropractor faces firestorm for cracking newborn baby's back

Shocking video has surfaced showing an Australian chiropractor appearing to crack a newborn baby's back.

Treatment of the baby, who had colic and was only 4 days old, is prompting a firestorm of controversy as doctors weigh in on either side.

One doctor said on Fox and Friends Weekend this morning that the treatment is not as dangerous as it may sound - and "works really well with calming babies."

"The noise you hear is gas being released from the joint. It's a fairly normal thing," said Dr. Tim Bain of Bain Complete Wellness. "You're not cracking the back, per se."