India's top anti-terrorism investigation agency Friday again sought the death sentence for a leading Kashmiri independence figure and former rebel leader after he was given life in prison, official sources said.

Muhammad Yasin Malik, 57, chief of Jammu Kashmir Liberation Front (JKLF), pleaded guilty last year to funding terrorism after refusing to accept a government-appointed lawyer or to defend himself against the charges.

The court turned down a plea by the National Investigation Agency for a death sentence, saying capital punishment was for a crime that "shocks the collective consciousness" of society.

On Friday the NIA petitioned the High Court in New Delhi again seeking death sentence for Malik, a senior security official in Indian-held Kashmir told AFP.

The petition is due for hearing on Monday, legal news website Bar and Bench reported.

Malik's JKLF spearheaded an armed insurgency in 1989 in the Indian-controlled portion of Kashmir, a part of which is administered by Pakistan since 1947, seeking independence for the entire former kingdom from both countries.

India responded with a massive military campaign and the conflict has left tens of thousands of civilians, soldiers and rebels dead.

Malik renounced violence in 1994 to campaign peacefully for independence, meeting with Indian leaders including two prime ministers over the following years.

He was repeatedly jailed, spending 14 years in prison where he claimed he was tortured, and was finally arrested in 2018, months before New Delhi cancelled the restive region’s semi-autonomy, imposing a lockdown and communications blockade lasting months.

Tension has simmered in the Muslim-majority region since, with many accusing Hindu nationalist Prime Minister Narendra Modi of seeking to change its demographic balance.

Malik rose to prominence in 1990 when his group abducted the daughter of India's interior minister and released her in exchange of five colleagues from Indian prisons.