The Nigerian army has carried out raids on distribution centres handling several of leading national newspapers.
The newspapers said their delivery vans had been searched and vendors questioned across the country, and copies of the papers destroyed.
The move has been condemned as censorship by the newspapers and international media groups.
But defence officials said it had been a routine security operation and denied confiscating copies.
The Nigerian government and President Goodluck Jonathan are facing public pressure to do more to tackle a bloody insurgency by Islamist Boko Haram militants in the north.
The group has attacked the army, media and civilians, and staged kidnappings including that of more than 200 girls from a school in Chibok in April.
The raids come days after Nigeria’s Information Minister, Labaran Maku, warned the media not to give “free publicity”, saying they must “define the lines between the urge to report and the need to protect the interest of our nation”.
‘Orders from above’
The Leadership, Punch, Nation, Daily Trust and Vanguard newspapers said the raids were carried out on Friday and Saturday.
An editorial in Punch said one of its distributors witnessed “a group of heavily armed soldiers” storming the cargo area of the Murtala Muhammed international airport in Lagos and searching all the editions waiting to be sent out.
The commanding officer said they were acting on “orders from above”, said the paper, adding that papers were prevented from entering Ekiti, Oyo, Osun, Ondo and Edo states.
The Nation said soldiers told its distributors they were acting on reports that attackers were attempting to use the newspaper distribution system to “ferry explosives to wreak havoc”.
“They were civil but they gave us stern instructions not to attempt to distribute our copies,” said the unnamed man.
Witnesses said delivery drivers had their mobile phones confiscated and were not allowed to take the newspapers when they left.
The Daily Trust said some of its vendors were arrested, and that a senior military figure there had accused the media of “publishing and selling falsehood”.
It said the raid followed a report it published on Friday accusing senior army figures of using army land for personal use.
Army spokesman Gen Olajide Laleye told Agence France Presse that while vehicles were being searched “we are not preventing any newspaper from being distributed”.
Another spokesman, Major Gen Chris Olukolade, said the operation was not intended to infringe on the freedom of the press but to prevent the distribution of materials with serious security implications.
But the Nigerian Guild of Editors said the media “do not bear arms but rather we bear information”, and likened the operation to the censorship the media faced when the country was under military rule.
Sue Valentine of the Committee to Protect Journalists warned that denying access to news “sows the seeds of rumours and distrust”.
“While we recognise that Nigeria faces security threats, these can never effectively be addressed by media blackouts or persecution of journalists,” she said in a statement.
“We call on authorities to respect the vital role that media play in circulating information and holding government to account.”
Who are Boko Haram?
- Founded in 2002
- Initially focused on opposing Western education – Boko Haram means “Western education is forbidden” in the Hausa language
- Launched military operations in 2009 to create Islamic state
- Thousands killed, mostly in north-eastern Nigeria – also attacked police and UN headquarters in capital, Abuja
- Some three million people affected
- Declared terrorist group by US in 2013