SRINAGAR, India—A little-known Kashmiri separatist leader is spurring stone-throwing protests against India with tactics such as YouTube recruitment videos and protest calendars published in local media, fostering protracted violence that is bedeviling New Delhi.

In an interview, the leader, Masarat Alam Bhat, 39 years old, said these protests would intensify after the Muslim holiday of Eid-ul-Fitr, which this year falls around Sept. 10, unless India offers major concessions to appease protesters who want Kashmir to be its own nation or part of Pakistan.

Separatist demonstrations erupted this summer in the Indian-held portion of Kashmir, an area that was split between India and Pakistan in 1947 but that remains claimed in its entirety by both. Indian security forces countered violently, with more than 60 civilians killed since mid-June.

The government says publicly the protests are either backed by Pakistan, which has fought two wars with India over Muslim-majority Kashmir, or are spontaneous and leaderless. But Mr. Bhat conveys a picture of a movement that is home-grown and highly organized.

"We are hopeful and sure we will win this war," Mr. Bhat, who rarely speaks to media, said from a location in Srinagar, the summer capital of India's Jammu and Kashmir state. He said he changes location every few hours to avoid arrest on charges of inciting violence. He said he isn't backed by Pakistan.

Mr. Bhat uses the Internet to spread his call to rise up for secession; in July, he made an impassioned video appeal, posted on YouTube, for Indian troops to leave the valley.

Perhaps his most significant innovation has been a "Protest Calendar" published in the local media that stipulates days for protests and closures of schools and shops. The calendar, which has largely been adhered to by both rural and urban Kashmiris, has brought the valley to a virtual economic standstill.

"People are all against India now. They will do anything," he said. "They will sacrifice anything."

The protests have largely been low-tech, with mostly young people turning out and throwing stones at Indian forces. No Indian security personnel have died, marking something of a public-relations victory for the protesters.

"Mass mobilization has happened before but never so systematic, never for so long and never so widespread. He's strategized it," says Sheikh Showkat Hussain, a law professor at the University of Kashmir.

Kashmir's new inspector general of police, S.M. Sahai, says authorities are seeking Mr. Bhat for playing a central role in the protests. He says he believes Mr. Bhat's core supporters, unemployed youths aged under 25 years old, have intimidated other Kashmiris to shut down schools and shops but that many are now tired of the closures.

A senior Indian Home Ministry official said Mr. Bhat was more radical—and has a larger support base—than other separatist leaders. "He represents the extreme form of Islamism in Kashmir," the official said, adding that his tactics will be fruitless: "We're not giving in to threats. There's no chance."

Mr. Bhat—a science graduate who speaks fluent English and wears a long, unkempt beard in the Islamic fashion—is the leader of a separatist party called the Muslim League. He is also the deputy of the hard-line faction of the All Parties Hurriyat Conference, a separatist group with conservative, Islamist leanings that rejects talks with India on Kashmir's status.

His group split off years ago from more moderate members, who back talks with India. Mirwaiz Umar Farooq, the leader of the more moderate splinter group, says the conservative movement has broad influence. "He's become an icon, a Robin Hood-type figure," Mr. Farooq says.

But Mr. Farooq says Mr. Bhat's non-stop strikes and other methods have filled young people with unrealistic expectations for independence. He also says Mr. Bhat has attempted to portray Kashmir as a religious battle between the local Muslim-majority population and Hindu-majority India. "He took a radical line in terms of Kashmir being an Islamic issue," he says. "We see it as a political problem."

The issue of Kashmir is crucial to regional peace and even the U.S.-led war in Afghanistan.

During the 1990s, more than 60,000 people died in a struggle between militants, trained and funded by Pakistan, and security forces. India largely stamped out the rebellion using hundreds of thousands of troops.

India maintains more than half a million security forces in its part of Kashmir, creating a sense of military occupation. The U.S. believes the tensions are a major reason Pakistan doesn't deploy more troops to fight Taliban militants on its Afghanistan border.

In 2008, elections in the Indian state of Jammu and Kashmir, for which two-thirds of the electorate turned out, led to hope that separatist tensions had declined. But separatist parties, including Mr. Bhat's, boycotted those polls, saying they were illegitimate. The failure of the pro-India state government to push through election promises, most importantly a demilitarization of Kashmir, boosted support for separatist politicians.

Mr. Bhat came to the fore just before those elections as a spokesman for separatist parties during mass protests in mid-2008 against the transfer of Kashmiri land for use by Hindu pilgrims. Police fired on those protests, killing scores of people.

Mr. Bhat became active in student politics in the late 1980s, after graduating from Srinagar's top Protestant missionary school. He said he has spent 17 years of the past two decades in jail for separatist activities but never fought as a militant. Police and Indian state officials confirm that account, saying he has been arrested only for unrest.

He was released from his latest stint in jail just before June 11, the day police fired tear gas shells to disburse a separatist demonstration in downtown Srinagar, killing a college student and igniting the current round of violence. Mr. Bhat quickly began organizing protests.

He acknowledges that he favors Kashmir ceding to Pakistan, an Islamic state, and believes the Quran should serve as the basis for law in the territory. Mr. Sahai, the police chief, says he has evidence Mr. Bhat's Muslim League receives funding and support from Pakistan-based Islamist groups. Mr. Bhat denies he has ties to Pakistani-based militant organizations or other global Islamist groups. He says he respects non-Muslims.

"We are not having an international agenda. We are not against America. We are against Indian occupation," says Mr. Bhat, sitting on the floor of a sparse room in a two-story brick house in Srinagar's old town, a warren of narrow lanes overlooked by a Mughal-era fort.

A supporter locks the door from outside. Mr. Bhat says he has been able to evade capture for three months because India's intelligence apparatus has broken down amid the protests. "If I'm at large it's because of the people," he says, speaking softly and averting his eyes.

Mr. Bhat says that for the current violence to stop, India must first agree that Kashmir is an international dispute and hold a plebiscite over the future of the territory. It must also take measures such as withdrawing troops and reforming a law that shields Indian security forces from prosecution for human-rights abuses.

The government has intimated in recent weeks it is willing to offer limited compromises, such as revisions to army-impunity laws and some troop draw-downs, but only after the current round of violence is quelled.