A leading journalist and editor who worked for peace in the disputed Himalayan region of Kashmir has been shot dead along with his bodyguards.

Shujaat Bukhari had just left the Srinagar city office of his newspaper, Rising Kashmir, on Thursday when three men on a motorcycle fired at him and his two guards, police said.

Bukhari, 50, was hit multiple times in the head and abdomen and taken to hospital where he was pronounced dead around 7.30pm, police confirmed.

He is the first journalist to be killed in 12 years and the 14th since 1990 in Kashmir, a mountainous region fought over by India and Pakistan and claimed in full by both.

Police have released CCTV footage of three unidentified men who they said were responsible for the “terror attack”.

Militant groups in the Indian-controlled part of Kashmir have fought a three-decade insurgency against India and its perceived allies but none claimed responsibility for the attack.

Rising Kashmir, which Bukhari founded in 2008, was among the newspapers to have its printing press shut down in 2016 after the killing of a popular militant triggered months of street protests in which nearly 100 civilians were killed and thousands were blinded by pellets fired by the police and Indian paramilitary officers.

Bukhari wrote for the BBC at the time that journalists in Kashmir “had to work on a razor’s edge in what is effectively the world’s most heavily militarised zone”.

“Threats to life, intimidation, assault, arrest and censorship have been part of the life of a typical local journalist,” he said. 

“If a local journalist reports an atrocity by the security forces, he risks being dubbed ‘anti-national’. Highlighting any wrongdoing by the militants or separatists could easily mean that he is ‘anti-tehreek’ (anti-movement) or a ‘collaborator’.”

Ishfaq Shah, a subeditor at Rising Kashmir, told the Guardian Bukhari had just left the office when staff heard gunshots. They first assumed they were firecrackers being set off in anticipation of the Islamic festival of Eid-al-Fitr. “Then they looked out the window and saw people running,” he said.

After Bukhari’s death was confirmed the “devastated” staff returned to the office and worked to finish the day’s edition with a new front page about their editor. “We did it as a tribute to him,” Shah said. “We were taught by this man to do that.”

A witness said that he rushed to the area after hearing shots and found the editor slumped in his car. “I could only hear his driver murmuring,” he said.

A police official at the scene said: “It appears to be a very well-planned attack. The attackers knew the routine.”

police sources have speculated the killing might be related to Bukhari’s involvement last August in a private peace-building initiative involving activists and members of the Indian and Pakistani governments. Senior militant leaders had criticised Bukhari and other Kashmiris involved in the proceedings.

The journalist had been given five security guards by the government after a murder attempt in 2000. Three were understood to be posted to his home and two travelled with him.

Bukhari’s killing took place amid a push by Delhi to initiate a peace dialogue in Kashmir. A temporary, unilateral ceasefire announced by the government for Ramadan ends on Friday.

The Indian home minister, Rajnath Singh, called the editor’s killing “an act of cowardice”. 

“It is an attempt to silence the saner voices of Kashmir,” he tweeted. “He was a courageous and fearless journalist. Extremely shocked [and] pained at his death.”

On Thursday, the UN released its first report on human rights violations in Kashmir, calling for an independent inquiry into allegations of murder, rape and torture committed by India and Pakistan.