Nigerian Television Authority (NTA) cameraman Alhaji Zakariyya Isa was killed in the north-eastern Nigerian city of Maiduguri on Saturday, apparently by members of the Islamist Boko Haram group, according to reports citing the Nigerian authorities.

Two gunmen reportedly followed Isa, who worked as a Hausa translator and newscaster, from the mosque where he had just finished praying to his nearby house and then opened fire on him, according to local news reports. He was buried on Sunday.

The Nigerian Union of Journalists condemned the killing, and called on the authorities to “bring his killers to book,” AFP reported.

It is not yet clear whether Isa was killed as a result of his work as a journalist or his affiliation with the Nigerian Television Authority (NTA), which is owned by the government.

Recently, violence has escalated in Borno state. Just one day after Isa’s death, a bomb blast reportedly hit a military patrol in the city. Boko Haram has claimed responsibility for many of the recent attacks, including the bombing of United Nations headquarters in Abuja, the capital, in August this year.

In September, Boko Haram reportedly threatened to attack media organisations, which they said had misrepresented them to the public.

IPI Press Freedom Manager Anthony Mills said: “We send our heartfelt condolences to Mr. Isa’s family, his colleagues and his friends, and urge the authorities to bring his killers to justice. The killing of journalists is the most brutal form of censorship. All of society pays the price when journalists are silenced.”

Isa is the first journalist to be killed in Nigeria this year, according to the IPI DeathWatch.