Istanbul: A German reporter was prevented from entering Turkey on Tuesday and was held in a deportation room at Istanbul’s Ataturk Airport before he was sent back to Cairo, according to a Turkish official and a German broadcaster.

German public broadcaster SWR wrote on Twitter that its correspondent Volker Schwenck had landed in Cairo, his base, after being detained for several hours in Turkey. A Turkish official confirmed he was sent back to Egypt saying the decision was an “individual matter.”

SWR is part of the ARD network, one of two main public broadcasters in Germany. Another of ARD’s members recently aired a song poking fun at Turkish President Recep Tayyip Erdogan, triggering a diplomatic rebuke from Turkey.

The Turkish official, who spoke on condition of anonymity because he wasn’t authorised to speak publicly about the matter, pointed out that ARD TV has an office and full-time staff in Istanbul and said the decision to expel Schwenck was not a “reflection on their journalistic activities”.

He did not say why the journalist was banned from entering.

Earlier in the day, Chancellor Angela Merkel said her government was concerned about the detention of the German television reporter, adding that diplomats were trying to resolve the situation.

Asked about the incident during a news conference in Berlin, Merkel said German officials “immediately looked into the matter.”

“The Foreign Ministry in particular is in constant contact with all necessary authorities and is of course trying to restore the journalist’s ability to work. As such we are pursuing this and regard it with some concern.”

It is the latest incident involving journalists to sour German-Turkish relations.

Last week, Merkel’s government granted a Turkish request to allow the possible prosecution of a German TV comic for writing an intentionally offensive poem about Turkish President Recep Tayyip Erdogan.

Critics of the decision accused Merkel of giving in to Turkish pressure because of Ankara’s key role in halting the flow of migrants to Europe.

The poem by comedian Jan Boehmermann was a response to Turkish anger over a satirical programme on one of SWR’s sister channels that had also poked fun at Erdogan.

Last month, German weekly Der Spiegel pulled its correspondent from Istanbul, saying Turkey had refused to renew his press permit.

Another Turkish official said Schwenck was banned from entering Turkey because of a previous incident but gave no details.

“He knew he would not be allowed in, yet he still came,” said the official, who spoke on condition of anonymity because he is not authorised to discuss the issue publicly.

A spokesman for SWR denied the official’s version.

“There had never previously been problems. It’s the first time he’s faced such a situation,” Wolfgang Utz told The Associated Press. “He wasn’t aware of any entry ban.”

Schwenck, who had planned to travel to the Syrian border to interview refugees, posted a picture on Twitter of a document titled “Inadmissible Passenger Notification Report”.

He tweeted: “Final stop Istanbul. Entry to Turkey denied. There’s a note with my name. I’m a journalist. A problem?”