KANO Islamist group Boko Haram released a video late on Tuesday celebrating its bombing of a Nigerian newspaper and warning of more attacks on local and foreign media if they published reports that were biased to the sect or insulting to Islam.
Suicide car bombers targeted the offices of This Day in the capital, Abuja, and northern city of Kaduna last Thursday, killing at least five people in apparently coordinated strikes.
Boko Haram has been fighting a low-level insurgency for more than two years and has become the main security threat facing Africa's top oil producer, although most attacks have been in the largely Muslim north, far from southern oil fields.
The sect, which wants to impose an Islamic state on Nigeria's more or less evenly mixed population of Muslim and Christians, has been blamed for hundreds of killings since its uprising against the government in 2009.
It had not previously targeted the press in its bombing campaign, although last October it killed a reporter for state TV who the sect said was an informant to President Goodluck Jonathan's administration.
The video posted on the Internet opens with a Koranic song and a drawing of the Koran sitting on two crossed AK-47s. A banner in the northern Hausa language says:
"Message from Jama'atu Ahlis Sunna Lidda'awati Wal-Jihadl (Boko Haram's full name): on why we attacked ThisDay".
It then plays a video tape shot from a distance of the ThisDay Abuja office, which promptly explodes into a ball of flames and grey smoke - that suggests the sect had a cameraman set up in anticipation of the strike.
"We attacked Thisday because we will never forget or forgive anyone who abused our Prophet," a voice booms in Hausa.
ThisDay angered Muslims a decade ago when one of its columnists suggested the Prophet Mohammad might have wanted to marry a beauty queen, an event to which the tape alludes.
The statement rages against local and international media for carrying reports by Nigeria's government that a faction of the sect was behind the kidnapping of two hostages - one British, the other Italian - who were killed by their captors during a botched March rescue attempt.
"We said we have nothing to do with it, yet these media houses reported that we were responsible for the incident," it said, also complaining about reports, which it denied, that its spokesman Abu Qaqa had been captured.
It warned it would attack other media houses soon, listing several local papers as next on the list and several international media as "on the verge of jointing them".
It was at least the fifth video that Boko Haram had posted this year, mostly from self-proclaimed leader Abubakar Shekau. Shekau appears in this one, too, waving an AK-47 around.
From being a secretive sect in the shadows, the group has gradually raised its media profile, which may explain both the proliferation of home videos and growing attacks on media.
A spate of attacks in the past few days, including one against Christians in the north that killed 19 people on Sunday, dampened hopes that tighter security in the north had drastically reduced the sect's capability.
Nigerian forces raided the hideout of Islamist militants in Kano on Tuesday, killing the suspected mastermind of an attack on Christian worshippers in a gun battle that lasted several hours in the main northern city.
(Writing by Tim Cocks; Editing by Paul Simao)