Most of the shops, fuel stations and other business establishments in Srinagar, the summer capital of the state, were shut, while public transport was minimal, officials said.
The effect of the strike was accentuated by a public holiday in Kashmir today, they said.
Reports of shutdown were also received from most of the other district headquarters of the Valley, the officials said.
They have extended the protest programme till the end of this month and have asked people to observe shutdown on Fridays and Saturdays.
The separatists have been spearheading the agitation since the killing of Hizbul Mujahideen commander Burhan Wani in an encounter with security forces in south Kashmir on July 8.
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Meanwhile, clashes broke out between protesters and security forces in several parts of the Valley including Nowhatta after Friday prayers, police said.
He said the security forces, posted on duty to maintain law and order, fired tear smoke shells to disperse the protesters.
The protesters resorted to stone-pelting at the security forces, the official said.
Reports of similar clashes were received from Sopore in north Kashmir and Newa in Pulwama district of south Kashmir, he said.
There were no report of any casualty in the clashes, he said.
