Award-winning Pakistani journalist and novelist Mohammed Hanif says copies of his best-selling satirical novel A Case of Exploding Mangoes have been seized.
The book, which was recently translated into Urdu, pokes fun at the country's former military dictator, General Zia ul-Haq, and others in the armed forces.
It was first published in English over a decade ago to critical acclaim.
Hanif said security agents seized stock from his Karachi publishers and bookshops in Islamabad and Lahore.
Last month, the former BBC journalist received a defamation notice from Gen Zia's son.
Who seized the books?
Men who identified themselves as agents from Pakistan's Inter-Services Intelligence (ISI) turned up at the offices of the Maktab-e-Danyalpublishing house on Monday, Hanif said.
"They claimed to be from the ISI but did not produce any official ID to prove that. They just took away all copies of the book," he told BBC Urdu.
"They hurled threats at the manager of Maktab-e-Danyal, sought information about me and said they'll come back to get lists of outlets to which the book has been supplied. It looks like they want to scare the few people who still want to read old books."
A Case of Exploding Mangoes has been in publication for 11 years now. Nobody has ever bothered me. Why now? I am sitting here, wondering when will they come for us. ISI is World’s No 1 spy agency. I am sure they have better things to do. I have my school run tomorrow. 3/3— mohammedhanif (@mohammedhanif) January 6, 2020
Men had also raided a major Islamabad book store, Saeed Book Bank, as well as Fiction House in Lahore, he said.
The BBC contacted the Pakistani military but has so far received no response to allegations that members of its intelligence service were involved.
An unnamed official at the ISI told the Associated Press the claim was a "cheap attempt to gain popularity by hurling false accusations on a national institution".
Hanif, who was an air force pilot before turning to journalism, became famous when his novel was first published in English in 2008. It charts the last days of Gen Zia, who was killed in a mysterious plane crash in 1988.
The results of an investigation into the crash, which also killed the US ambassador, were never released and conspiracy theories have proliferated ever since. Exploding Mangoes centres on a rumour that a crate of mangoes gifted to Gen Zia contained a bomb which blew the plane up.
There were glowing reviews internationally and the novel made the Booker Prize long list. Since then, Hanif has established himself as a leading columnist on matters in Pakistan, including criticism of the army.
But despite praise for his first book, it did not go on sale in Urdu until November last year. By then it had been translated into major languages around the world, and many thought an Urdu edition was overdue.
However, the Urdu edition, which has been promoted at book fairs around Pakistan and is likely to have been read by a wider circle of people, is seen as more of a challenge to the military.
The last decade has seen a shrinking space for critics of the army in Pakistan, which has a history of coups. Efforts by the military to control the public narrative have increased in recent years at the expense of elected politicians, analysts say.