Srinagar, Dec 30 (PTI) Police on Wednesday claimed to have killed three militants in an overnight encounter in the city's Parimpora area but families of the slain youths said they had no connection with militancy and that two of them were students.

The families from south Kashmir's Pulwama and Shopian districts also staged a protest outside the police control room here and claimed that of those killed, one was a Class 11 student, one a university student and the other a carpenter.

While one militant was killed in the early hours of Wednesday, two others were shot dead a few hours later, a police spokesman said.

The three unidentified militants were killed in the overnight encounter in the Parimpora area of the city. Militants had opened fire on security forces during a cordon and search operation on Tuesday evening, he said.

Cordon was strengthened and there was an exchange of fire between the two sides. Firing went on throughout the night intermittently, the spokesman said.

Police have yet not released the identity or age of the slain youths, but the protesting families claimed that the youths were their kin and had no connection with militants or militancy.

The slain youths were Athar Mushtaq and Aijaz Maqbool, both students, and Zubair Ahmad, a carpenter, said the families, but did not disclose how old they were.

"My brother left for university at 11 am yesterday (Tuesday) as he had to fill some form there. He called me at 3.01 pm to say that he might have to stay at the university. Today, we got a call that he has been killed. He was not a militant," Maqbool's sister told reporters.

Maqbool is the son of policeman who is posted in Ganderbal district, she said.

A relative of Mushtaq also made a similar claim and said he was just a teenager studying in Class 11.

Police officials did not respond to queries about the claims made by the families.

However, an army official said the slain youths were "hardcore terrorists" who used a lot of ammunition and grenades against the security forces during the encounter.

"We made several appeals to the youths to surrender. One of them was about to leave the building but his colleagues fired and hurled grenades at security forces and pulled him back yesterday. In the morning, we again made appeals to them to surrender but we realised that they were not going to surrender," the official said.

"The quantity of ammunition they used makes it clear that they were planning to carry out a major terror strike in the area," the army official added.