Attackers killed three people today at a publishing house that had been the subject of protests for distributing Bibles in Turkey, the government-run Anatolia news agency reported.
One person who had his throat cut inside the publishing house and another died after jumping from the second floor to escape.
Other staff were taken to local hospitals for treatment, the private Dogan news agency said.
Anatolia said one of those taken to the hospital later died.
Nationalists had previously protested outside the Zirve publishing house in the city of Malatya, accusing it of proselytising, Dogan reported.
Video footage showed one man being tackled by police outside of the building, and another in a neck brace being loaded into a stretcher.
Malatya is known as a hotbed of nationalists and is the hometown of ultranationalist Mehmet Ali Agca, the Turkish man who shot Pope John Paul II in 1981.