Bicycle Thief/Thieves

This has been confusing me for sometime now and I was reminded of it during the Oscars last night. Criterion is releasing Vittorio De Sica's masterpiece but the title has changes from The Bicycle Thief to Bicycle Thieves. During the montage of Best Foreign Language winners last night the title was shown as the former, and every time I've seen the movie it has always been referred in the singular. In the context of the movie the plural makes more sense, but when did the title change?