Was the Book of the Law (Torah) ever kept inside the Ark of the Covenant? Deuteronomy 31:24-26 (NIV) After Moses finished writing in a book the
  words of this law from beginning to end, he gave this command to the
  Levites who carried the ark of the covenant of the Lord: “Take this
  Book of the Law and place it beside the ark of the covenant of the
  Lord your God. There it will remain as a witness against you.


This verse indicates that the Torah was placed beside the Ark of the Covenant and stood there as a  witness.  But this Wikipedia mentions the Torah as once kept inside the Ark.

Was there any chance ever that the Torah was kept inside the Ark? Is there any verse supporting it? (If the information in Wikipedia is not credible, someone must update it)

Note: Readers should not be confused between Torah (book) and the stone tablets (10 Commandments). The question here is about the Book, not the tablets.
The rabbis debate the meaning of the verse in Bava Batra 14b. מִצַּד is a rare combination, but it certainly means "beside" in Jos. 3:16, Jos. 12:9, Ruth 2:14, 1 Sam. 20:25. I see no instances where it can unequivocally be asserted to mean "in," "inside," or "within." Had Moshe intended to say that it was placed "inside" the Ark, why wouldn't he have written ב or בקרב instead?

For example, using the same verb that is found in Deut. 31:26 (a conjugation of the verb שׂוּם, meaning "to put" or "to place"), Isaiah writes (Isa. 63:11),


  ...Where is He who put His Holy Spirit within him?


The prophet uses the prepositional phrase בְּקִרְבּוֹ (bekirbo). The context makes it clear that God puts or places His Holy Spirit inside an individual.

Another example is Deut. 10:2 where we find, again, the same verb, but this time, Moshe uses the prepositional prefix ב. 


  And I will write on the tables the words that were on the first tables which you broke, and you shall put them in the Ark.


Here, God commands Moshe to put the tables (which have the Ten Commandments written upon them) in the Ark, which is translated from the Hebrew phrase בָּאָרוֹן (ba'aron).

So, the tablets are placed בָּאָרוֹן, "in the Ark." Why not write the same for the Torah scroll if indeed it was located "in the Ark"? There's simply nothing which explicitly confirms that it was indeed located in the Ark. Again, the prepositional phrase מִצַּד is never used in a context meaning "inside" or "in."