NFL lineman D.J. Fluker has brought in extra security to keep both himself and his daughter safe from the child's mother after she was arrested for kidnapping, TMZ Sports has learned.

We're told the Baltimore Ravens lineman has been working with the team to coordinate security in the wake of the arrest -- though it's unclear if the Ravens are footing the bill or just providing guidance.

We're told the team is being very understanding about the situation.

As we previously reported, Fluker's ex, Kimberly Davis, was arrested on Sept. 22 after allegedly kidnapping their daughter during a supervised visit while Fluker was out of town to play the Houston Texans.

TMZ Sports has obtained a photo of the moment Davis was taken into custody.