Where does the AWS EFS backup get stored?

I am backing up my EFS using AWS Backup service. Wanted to know where the Backup is actually stored? Is this getting stored in the EFS itself or not? I noticed a huge hike in the data stored in the EFS so wanted to know if the automated backup can be causing this hike or not, I tried deleting few backup recovery points from the backup vault but is not making much of a difference.

Thanks in advance for your help.

Your backups are not stored on your EFS itself. They are stored in Recovery points in a backup vault. Term Recovery point is interchangeable with backup according to aws docs. you need to check you application etc which stores data on efs or check efs itself what has been added which has caused this hike.