KHOST, Afghanistan (Reuters) - An Indian author whose story was told in the movie "Escape from Taliban" was shot dead after returning to Afghanistan to make a documentary about women, police said on Friday.

The killing of Sushmita Banerjee, 49, on Wednesday was the latest in a series of attacks on women in the conservative Islamic country, adding to concern that hard-won women's rights are eroding ahead of next year's withdrawal of most international forces.

The Afghan Taliban denied involvement.

Banerjee, who told her story of life under the Islamist Taliban in "A Kabuliwala's Bengali Wife", was dragged from her house in lawless southeastern province of Paktika and shot as many as two dozen times, police said.

Her body dumped close to a nearby Islamic school, Paktika police chief General Dawlat Khan Zadran said.

"Gunmen entered her house at 11 p.m. on Wednesday, took her out and shot her dead," Zadran said, adding that he suspected Taliban involvement.

The gunmen had bound her and her husband before taking her away, he said. Her husband was badly beaten.

"No-one has been arrested and we are speaking to her family about what happened," Zadran said.

A spokesman for the Taliban, Zabihullah Mujahid, denied involvement. The group has been waging an insurgency against the U.S.-led military in Afghanistan since its ouster from power in 2001.

During their 1996-2001 reign, the Taliban banned women from education, voting and most work, and they were not allowed to leave their homes without permission and a male escort.

Banerjee, from Kolkata, moved to Afghanistan in 1989 after marrying Afghan businessman Jaanbaz Khan. She converted to Islam and changed her name to Sayed Kamala.

She opened a dispensary providing medicine, but her life changed dramatically in 1993, when the Taliban emerged in southern Afghanistan after years of war.

Branded a woman of poor morals, she was forced to close her dispensary and whipped for refusing to wear a burqa, she said in her book.

She fled to Pakistan but was brought back by her husband's family and kept under house arrest. According to her book, she escaped in 1994 by tunnelling a hole through the house's mud wall.

She fled but was quickly detained near Kabul. Despite threats of execution, she convinced the Taliban to send her to the Indian embassy from where she was repatriated to India.

Her story was made into a Bollywood film, "Escape From Taliban", in 2003.

Banerjee was making a documentary about the lives of women in Paktika when she was killed, said the head of Afghanistan's National Journalists' Union, Faheem Dashty. And she was intending to write another book about Afghanistan, her Indian publisher, Swapan Biswas, told Reuters.

"She was sad that she had nothing to offer in the book fair in Calcutta earlier this year and she told me she planned to go to Afghanistan to gather material for a new book," he said.

"It is so sad, and so shocking," said fellow Bengali writer Shirshendu Mukhopadhyay. "I see this as a kind of martyrdom. She was a brave woman and had been working for women there."

The attack was the latest in a series of high-profile attacks on women, including the abduction of female MP Fariba Ahmadi Kakar last month and the shooting death of a prominent Afghan policewoman in the southern Taliban heartland city of Kandahar in July.

The killing is likely to anger Indians, following last month's attempted bombing of the Indian consulate in Jalalabad.

(Reporting by Elyas Wahdat in Khost and Sujoy Dhar in Kolkata; Additional reporting by Mirwais Harooni and Dylan Welch in Kabul; Editing by Nick Macfie)