Karwan or Kawran ?

The above two names describe the same place of the city. But nobody seems to care about the accurate or correct name. Most of the people spell it as Kawran Bazar, however, the media house that publishes the two dailies with the largest circulations, "Prothom Alo" and "The Daily Star" seems to prefer the former name. Obviously, they have logic behind the use of a different spelling.
Will some one enlighten us about it?