Chautauqua, New York - Author Salman Rushdie was rushed to hospital for surgery after being attacked during a literary event in New York state on Friday.

The 75-year-old was transported by helicopter to the hospital for surgery, but his overall condition remained unclear. He was stabbed at least once in the neck and the abdomen, according to police.

Rushdie's agent Andrew Wylie said his client was on a ventilator and could not speak, in an update cited by US media including the New York Times.

"The news is not good," he said. "Salman will likely lose one eye; the nerves in his arm were severed; and his liver was stabbed and damaged."

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The attacker stormed the stage at the event attended by hundreds of people around 11 AM and stabbed Rushdie, a police spokesman said.

Several event staff and spectators then rushed the suspect and brought him to the ground and a police officer arrested the 24-year-old male, he said.

Rushdie was treated by a doctor who was in the audience until rescue workers arrived and took the author to hospital by helicopter.

The attacker is thought to have acted alone, the spokesman said.

Rushdie was giving a lecture at a cultural center as part of a series titled More than Shelter, which intended to discuss the US as a safe haven for exiled writers and persecuted artists.

Because of his 1988 work, The Satanic Verses, a fatwa was issued against Rushdie by then-Iranian revolutionary leader Ayatollah Khomeini calling for the author's death. Some Muslims felt their religious sensibilities were offended by the work.

Whether Friday's attack was at all related to the decades-old fatwa was unclear.

Rushdie's publisher last year said the fatwa has long since stopped affecting the author's life, and that he is no longer restricted in where he goes and no longer needs bodyguards.

Rushdie told German magazine Stern days earlier that he felt safe in the US, and that the threat was from a long time ago.

Writers including JK Rowling and Stephen King expressed their horror at the attack. US writers' organization PEN America said it was "reeling from shock and horror at the word of a brutal, premeditated attack" on Rushdie.

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"Salman Rushdie has been targeted for his words for decades but has never flinched nor faltered," PEN America chief executive Suzanne Nossel said in a statement.

Rushdie was born in the Indian metropolis of Mumbai (then Bombay) in 1947, the year of Indian independence.

He later studied history at Cambridge University in Britain. He had his breakthrough as an author with the book "Midnight's Children," which was awarded the prestigious Booker Prize in 1981.

In it, he tells the story of India's detachment from the British Empire based on the life stories of protagonists who are born at the precise moment of independence and are endowed with supernatural abilities.

Rushdie has published more than two dozen fiction, non-fiction, and other writings overall.

His style is referred to as Magic Realism, in which realistic events are interwoven with fantastic elements.