A Dutch journalist who in January was acquitted by a Turkish court of writing propaganda for Kurdish militants has been detained in southeast Turkey "for her own safety" due to fighting in the area, a Turkish official said Sunday.

"I'm in custody in Yuksekova," Frederike Geerdink tweeted, adding that she had been travelling with a Kurdish protest group whose members were all also taken into custody.

A report by the Dutch news agency ANP said Geerdink had been arrested on suspicion of "travelling in a forbidden area."

But a senior Turkish official, who declined to be named, told Reuters: "Frederike has not been arrested for journalism. She was in a security zone where there was fighting. Because of that, we could not guarantee her safety, so she has been detained and investigations are continuing."

Geerdink, a freelance journalist based in the mainly Kurdish southeastern city of Diyarbakir, was arrested in January and accused of posting messages on social media in support of the outlawed Kurdistan Workers' Party (PKK).

Her arrest was decried by human rights and press freedom groups. She was acquitted of spreading illegal propaganda in April.

Dutch Foreign Minister Bert Koenders asked the Dutch embassy in Ankara to contact both Geerdink and Turkish authorities about the latest incident, his office said Sunday.

"The Netherlands has been concerned about freedom of the press and freedom of speech in Turkey for some time," spokesman Roel van der Meij said. "This remains an important point in our relations with Turkey."

The European Federation of Journalists urged Turkey to release Geerdink immediately.

Last week, a Turkish court freed two British Vice News journalists who had been arrested in southeastern Turkey on suspicion of having links to a terrorist organization, but kept their Iraqi fixer in custody.

The arrests caused an uproar from rights groups and raised fresh concern about press freedom at a time when Turkey is cracking down on Kurdish militants and taking on a bigger role in the U.S.-led coalition against ISIS in Syria.

The international Committee to Protect Journalists says harassment and prosecution of journalists have had a devastating impact on Turkey's media.

Kurdish militants have been clashing almost daily with security forces in southeast Turkey since July, when a two-year cease-fire between the PKK and the government collapsed, with both sides blaming each other.

Officials say that more than 70 members of the security forces and hundreds of Kurdish militants have been killed.

Geerdink wrote a book in Dutch on Turkey's Kurds and publishes an English-language blog called "Kurdish Matters."