Jan Boehmermann (C) attends the 1 Live Krone Awards | Patrik Stollarz/Getty Images German comedian under investigation for mocking Erdoğan Prosecutors say Jan Böhmermann and ZDF program directors have not been charged with any crime.

BERLIN – A comedian who recited a defamatory poem about Turkish President Recep Tayyip Erdoğan on German television is under criminal investigation along with his program directors, a German prosecutor said Thursday.

Jan Böhmermann called the Turkish president a “pervert," "zoophile,” and a "goat-f----er" in a poem read during the March 31 edition of his weekly late-night show “Neo Magazin Royale,” broadcast by German public broadcaster ZDF.

The ZDF program comes two weeks after another German public television network, NDR, aired a satirical song mocking the Turkish president's authoritarian style, which triggered a diplomatic spat between Ankara and Berlin. Turkish authorities protested with the Germans and demanded they delete the video posted on NDR's website.

In the NDR incident, Turkey’s foreign ministry summoned the German ambassador to Turkey to explain the satirical video, drawing even more international attention to Erdoğan's recent crackdown on free speech. German authorities, including Chancellor Angela Merkel, have defended that satire, calling it a matter of freedom of speech, guaranteed in German law and revered in the society.

The Böhmermann satire appeared to come in response to Erdoğan's complaint. In this case, however, ZDF removed the video from its online platform on its own, the day after airing it, saying it failed to meet the standard of satire programs.

On Wednesday, Andrea Keller, a public prosecutor in Mainz, where ZDF is headquartered, said her office has launched a criminal investigation into Böhmermann's televised recital after receiving 20 complaints against the comedian. On Thursday, she said the investigation has been expanded to include several of the ZDF program directors, after receiving complaints against them.

The prosecutors' move has sparked debate in Germany over the limits of free speech, with some critics saying that Germany looks more like Turkey. Others defended ZDF's decision to remove the video from its website, saying Böhmermann's poem was racist against Turks, who form the largest minority in Germany.

Böhmermann and the program directors have not been charged with any crime. Keller, the prosecutor, said her office checked with the German justice ministry in Berlin to see if Turkey had filed an official complaint against the comedian. However, it was not immediately clear if Turkey had done so.

According to legal experts, it's possible that only once this is done, and after the investigation is completed, could authorities charge Böhmermann and other ZDF staff with "defaming a representative of a foreign state."

If convicted, they could face up to five years in jail.

Merkel told Turkish Prime Minister Ahmet Davutoğlu in a phone call Sunday that the poem was "intentionally offensive," her spokesperson confirmed on Wednesday.

That same day, an internal review at the German foreign ministry concluded that a judicial investigation of the recent program is likely. However, Sawsan Chebli, a spokesperson for the foreign ministry, insisted that investigating the events does not imply that Böhmermann and the program directors had committed a crime.

“It’s not the job of the foreign ministry to make legal decisions whether the boundaries between the freedom of the arts and defamation were crossed," Chebli said. "This is up to high courts to decide.”

In Istanbul, a group of about 30 protesters gathered in front of ZDF's studio, throwing eggs at the building, according to Turkish media reports. ZDF confirmed the incident.

Turkish newspaper Sabah, which is owned by a company linked to Erdoğan, published an op-ed by Mikdat Karaalioğlu, the editor of its European edition, who addressed Böhmermann directly: “You bastard, you’re not a comedian, you’re a rabble-rouser,” Karaalioğlu wrote.