Four people were killed Monday when Indian security forces opened fire on stone-throwing protesters during fresh demonstrations against Indian rule in Kashmir, police said.

A total of 69 protesters and bystanders have been killed over the past three months, mostly by security forces who have used live ammunition on rallies after being pelted with stones.

The latest deaths, including that of a teenage student, occurred in Palhalan, about 30 kilometres (18 miles) north of the state summer capital Srinagar, police said.

"Security forces opened fire in self-defence after they were attacked with stones during a rally," a police officer said, asking not to be named.

He said one protester died on the spot while 18 others were wounded.

"One of the injured died on way to hospital," the officer said, adding that two more of the injured died in hospital.

He said the condition of two others was serious.

The fresh deaths brought more people onto the streets of Palhalan, chanting pro-independence slogans, a local photographer said.

They blocked the main highway and pelted stones at security forces and attacked government buildings.

Witnesses said the slain student was not part of the protest.

Residents told visiting reporters that security forces opened fire at peaceful demonstrations and that no one among the protesters hurled stones.

Authorities have launched a probe into the incident.

"Senior police officers have taken a serious view of the firing. Ammunition of the policemen is being checked to fix the responsibility," an official statement said.

"Those found involved shall be proceeded against strictly according to law without any favour," it said.

The killings also sparked protests in Srinagar and the southern towns of Pampore and Awantipora, witnesses said, adding hundreds of people poured on to the streets chanting, "Go India, go back!" and "we want freedom!"

The protests came as Muslims prepared for night-long prayers to mark a key night in the ongoing fasting month of Ramadan.

For nearly three months, crowds of young Kashmiris have defied curfews and pelted stones at the hundreds of thousands of security forces that India uses to keep a grip on the volatile region.

Last Monday, an 11-year-old boy was shot dead by police in the southern town of Anantnag during a violent demonstration against New Delhi's rule in the Muslim-majority region.

Government forces have struggled to contain the outpouring of anger ignited by the killing of a 17-year-old student by police in early June.

Protests began in the main town of Srinagar and have spread through the Kashmir valley.

In northern Handwara district, Indian soldiers Monday shot dead three suspected militants during a gunbattle, army spokesman J.S. Brar said.