Five suspected rebels were killed in Indian-administered Kashmir on Wednesday, police said, as relatives of two men shot dead during an earlier security operation demanded their bodies be returned.

Clashes between rebels and Indian government forces in the disputed Himalayan territory –- which is divided with Pakistan -– has claimed the lives of at least 140 militants so far this year.

The five were killed during two separate search operations by government forces in Kulgam district, police said in a series of Twitter posts.

The incident came the same day as a sit-in protest staged by relatives and neighbours of two men killed during the search of a commercial building earlier this week in Srinagar, the territory's main administrative hub.

Police said the men died in "crossfire" on Monday during a shoot-out alongside two suspected rebels also killed in the incident. 

But their families have accused security forces of murdering them in "cold blood" after taking them into a business centre to help search for insurgents.

"Today it happened to us, tomorrow it can happen to anyone," said Abdul Majeed Bhat, whose brother Mohammad owned the building and was killed in the incident.

"We'll not rest until my brother's body is returned to us," Bhat told AFP. "I appeal to every Kashmiri to protest for the same."

Security forces in Kashmir last year began refusing families access to the bodies of slain militants.

Officials say the practice helps stop "glorification" of anti-India rebels, whose funerals were usually attended by thousands of people.

After they were killed, the pair were hurriedly buried in the middle of the night by police in a remote graveyard, without their families present.

Give me my husband's body

Wednesday's protest continued after dark with a candlelight vigil, despite the freezing winter cold in Srinagar.

Friends and relatives of the two men deny they had links with militants. 

Humaira Mudasir, whose husband Mudasir Ahmed Gul was also killed Monday, was among the crowd and cradling her one-year-old daughter in her lap.

"Give me my husband's body. Give me proof of his involvement (with rebels). He was murdered unarmed," she told reporters.

Gul had rented an office in the building and was running a real estate business.

Police acknowledged in a Tuesday statement that they called the pair to "accompany" their search of the building, claiming they died in an exchange of fire with "terrorists".

They also accused both men of being associated with terrorist groups, and claimed one of the militants killed was a resident of Pakistan, without offering evidence for either claim. 

No member of the security forces was reported injured in the incident. 

Rebel groups have fought 500,000 Indian security personnel deployed in Kashmir for more than three decades to end Indian rule, with wide support from residents in the Muslim-majority territory.