In the letter, which ETC's editor-in-chief Andreas Gustavsson has published on X, Medin writes further that he "has only been engaged in journalism" and that it is not "something I should be imprisoned for".
"I still hope that this can be resolved quickly. I still want to believe that the pen is mightier than the sword", writes Medin.
The letter is dated April 12.
Joakim Medin traveled to Turkey to cover the extensive political protests in the country, but was arrested at the airport and has been imprisoned since March 27. The charges are not specified, but are said to involve involvement in a terrorist organization and insulting Turkey's President Recep Tayyip Erdogan.
Earlier in the week, Joakim Medin's appeal against the deprivation of liberty was rejected in a court in Ankara. According to the court, the suspicions of crime are strong.