Exodus 20:15

Strongs #1589 גנב ganab. to carry off, kidnap, deceive. "Stealing" is the "extended" meaning of this verb. But out of forty occurrences, the context of its usage is clear. It is used of carrying off animals, teraphim (Gen. 31:19), people, men, gods/goddess, beast, oxen, countrymen, sons, and the heart.

In 2 Samuel 19:3 a reflexive Hithpael is used, "The Gathered People are kidnapping themselves...."

Considering all the other commandments are related to people, it makes sense that this commandment would as well.