The journalist is being held in the tourist town of Kusadasi, according to her Twitter.
We gaan nu naar ander politieburo. Guvenlik buro amirligi in KUSADASI.ik heb het niet gehoord maar er isgefluisterd dat ik vast blijf zitten
— Ebru Umar (@umarebru) 23 April 2016
"Okay. Police are at the door. No joke," Umar said on her Twitter account late on Saturday.
Oké. Politie voor de deur timeline. Geen grap.
— Ebru Umar (@umarebru) 23 April 2016
The journalist has recently written a very critical review of Erdogan's activity for the Dutch Metro daily and tweeted some of the article's excerpts.
"I am not free, we are going to the hospital," she stated later, pointing at the medical examination ahead of appearing before the prosecutors.
According to the Dutch Foreign Ministry, Umar has been released.
TIMELINE! paar dingen: vrij maar heb landarrest. Later meer bij @metro @TPOnl @geenstijl pic.twitter.com/6W294EXkzv
— Ebru Umar (@umarebru) 24 April 2016
Earlier this week, reports emerged in the Dutch media, claiming the Turkish consulate in Rotterdam had emailed different Turkish organizations operating in the Netherlands with an appeal to report cases of Turkey's president being insulted.
Erdogan has been slammed for cracking down on his critics for a long time. Since becoming a president in August 2014, he has filed over 1,800 criminal cases against Turks for insulting him, according to the Turkish Justice Ministry.