Terrorists killed six Hindu pilgrims and wounded 14 others Monday in India-held Kashmir, police told AFP, after their bus came under attack.

India's Central Reserve Police Force, which provides security for the two-month long annual pilgrimage, said gunmen first opened fire on a security checkpoint but no injuries were reported.

“Militants further attacked the pilgrims' bus at Batingu (six civilians killed and 14 injured) and escaped towards Arwani,” the CRPF said in a statement.

The police force added the pilgrims were from the western Indian state of Gujarat.

A New Delhi based security official, speaking anonymously, told AFP that security personnel were exploring “all the angles including suspected Islamists”.

Hundreds of thousands of Hindu pilgrims trek over mountain trails to reach Amarnath caves, around 3,900 metres above sea level, in Indian Kashmir every year.

The devotees worship the natural ice formation at the caves as a symbol of Shiva, the Hindu god of destruction.

“Pained beyond words on the dastardly attack on the peaceful Amarnath Yatris (pilgrims) in Jammu and Kashmir,” Prime Minister Narendra Modi said on Twitter.

“India will never get bogged down by such cowardly attacks and the evil designs of hate,” Modi added. The pilgrimage has previously been the target of militants, with more than 30 pilgrims killed in 2000.

The state's former chief minister Omar Abdullah urged “every right thinking Kashmiri” to “unequivocally” condemn the attack.

“This is a moment for us to define ourselves. Are we willing to... take a stand. No terror and murder in our names,” Abdullah tweeted.

Mirwaiz Umar Farooq, head of All Parties Hurriyat (Freedom) Conference, a political coalition opposed to the Indian rule of Kashmir, also condemned the attack.

“As the unfortunate news of the Yatris killing reaches us leadership and people of Kashmir are deeply disturbed and saddened and strongly condemn it,” Farooq said on Twitter.

The chief minister of Jammu and Kashmir state said the attack was a “blot on all Muslims and Kashmiris”.

“Pilgrims come to Kashmir every year for the yatra despite all difficulties. And seven people died today. I have no words to condemn it,” Mehbooba Mufti Sayeed told reporters as she visited wounded victims in hospital.

Jammu and Kashmir, India's only Muslim-majority state, has since 2014 been governed by the pro-India People's Democratic Party in an unpopular coalition with Modi's ruling Hindu nationalist Bharatiya Janata Party (BJP).

Analysts say this has intensified public opposition to Indian rule in Kashmir.

Tensions have also been high around the first anniversary of the death of charismatic rebel leader Burhan Wani, who was shot dead by security forces on July 8 2016.

The death of the 23-year-old, who had built up a big following on social media, sparked a huge outpouring of grief in Kashmir.

Monday's attack was also codemned by separatist leaders in Kashmir also condemned the attack, which they said “goes against the very grain of Kashmiri ethos”.

“The annual Amarnath Yatra has been going on peacefully for centuries and is part of our yearly rhythm and will remain so,” they said in a joint statement.