The earthquake, measuring 6.2 on the Richter scale, occurred at 12.36 p.m. and its epicentre was the Afghanistan-Tajikistan border, Meteorological Office Director Manmohan Singh told IANS.
Officials said there were no immediate reports of loss to life or property. The tremors lasted a few seconds.
"We experienced a mild quake at around 12:30 today but no damage has been done and everything is safe," said Biranchi Narayan from Delhi.
With inputs from IANS
Lal Singh walked barefoot for nearly five hours after which his supporters urged him to get into a vehicle as he developed blisters in his feet.
The march was organised to mount pressure on the state government to have the Kathua rape and murder case investigated by the Central Bureau of Investigation (CBI).
Lal Singh and another senior BJP leader Chander Prakash Ganga resigned from the state cabinet following their participation in a rally organised by Hindu Ekta Manch in Hiranagar area in January this year.
The State Crime Branch has already filed a charge sheet against eight accused in the rape and murder of an 8-year-old in Rasana village of Kathua district.
On the plea of the victim's father, the Supreme Court has ordered that the trial of this case be held on a daily basis without any adjournment in Pathankot town of neighbouring Punjab.
Following a tip-off about the presence of militants in the area, security forces including state police and Central Reserve Police Force (CRPF) personnel surrounded Gasi Mohalla.
"One holed-up militant is still engaged in the gunfight with the security forces," police sources added.
A CRPF officer has been injured and internet services were suspended across the Srinagar district.
"No traffic will be allowed on the highway as road clearance operations are on at Battery Cheshma and some other parts of the road," a traffic department official said.
At least 2,000 vehicles were stranded at different places on the 300 km long road.
The valley-bound traffic was complaining that they have run out of money as shopkeepers and hotel owners have been charging them high rates.
Authorities said the highway was likely to be restored by Thursday afternoon.
However, nobody should undertake the journey before contacting traffic control rooms in Jammu and Srinagar city.
The trooper was wounded in the shootout as the security forces prepared for a final assault against the holed-up militants, a police officer said.
He was shifted to the nearby SMHS hospital, barely 300 metres away from the site of the gunfight, and died later.
It was the same hospital from where Pakistani LeT militant Naveed Jat alias Abu Hunzullah managed to escape on February 6 after killing two policemen.
Police said residents in the vicinity have been evacuated to safety.
Troops of the CRPF and the Special Operations Group (SOG) of Jammu and Kashmir Police were carrying out the operation against the militants.
Kashmir police chief S.P. Vaid in a tweet said: "I congratulate alert CRPF sentry for averting Suicidal attack in Karan nagar Srinagar. Fortunately two terrorists are in cordon & exchange of fire going on."
Earlier around 4.30 a.m., two militants were spotted by an alert sentry at the observation post of 23rd battalion of the CRPF in Karan Nagar area.
The two were forced to flee as the alert sentry fired at them.
Searches in the area revealed that the militants, carrying backpacks and AK-47 rifles, had taken shelter in a building near the CRPF camp, which was then surrounded.
After the hiding militants were challenged, they fired at the security forces triggering a gunfight, that is still on.
The attempted terror bid on the CRPF camp comes close on the heels of the Sunjuwan military camp attack, in which six people were killed.
Naveed Jat alias Abu Hunzullah escaped when the waiting militants fired at the police party outside S.M.H.S hospital.
A senior police officer said the militants were waiting outside the hospital to carry out the attack. Hunzullah was being taken to the hospital for treatment from Srinagar central jail.
The officer refuted media reports that the escaped militant had snatched the rifle of a policeman before escape.
The area around the hospital has been sealed.
Vehicles moving in the city are being searched to trace the escaped LeT militant who was arrested last year in south Kashmir's Shopian district.
The slain policeman has been identified as constable Mushtaq Ahmad. The injured policeman has been shifted to hospital.