The latest attack was at a bus stand in Tral in south Kashmir, where militants lobbed a grenade injuring seven civilians, according to agency reports.
Gunmen also fired at a search party in Soura in the outskirts of Srinagar and a grenade was hurled at a police station in Shopian.
Police sources said the troops, after receiving inputs on militant presence in Srinagar to disturb the upcoming poll rally of Prime Minister Narendra Modi , rushed to Srinagar's Untabhavan area, 8 km away from Lal Chowk.
An exchange of fire followed, and a top commander of the Lashkar-e-Taiba was shot dead, but the second one is still holed up in the neighbourhood, sources said.
Preliminary reports suggest the militants were travelling in a car before they entered a house in the Untabhavan area.
Militants kill 11 security men in Uri
The three attacks took place less than 12 hours after militants stormed an army camp at Mohra in Uri Tehsil, killing 11 security personnel.
Eight army personnel, including an officer and three policemen , including a sub inspector were killed in the attack on the ordinance camp. Six militants who carried out the attack were gunned down, army and police officials told Hindustan Times
"Terrorists opened small arms fire and lobbed grenades on the army camp at Mohura at 3am. Army response teams immediately mobilised and surrounded the area. Firefight continued till 9.30 in the morning and all terrorists were neutralised," an army official at the encounter site said.
"Casualties sustained by security forces during the operation are being ascertained. Injured have been evacuated to Baramulla and are stable. A search is still in progress," he added.
Defence minister Manohar Parrikar said all militants involved in the attack would be eliminated..
Sources said the attack on the ordinance camp was carried out by a group of three to four militants who are believed to have infiltrated in the Indian region a few days ago. Police and security persons have sealed the area and are not allowing any civilian movement.
Jammu and Kashmir chief minister Omar Abdullah said the attack was a "desperate attempt" to disrupt peace and normalcy.
"Once again shows the desperate levels militants will go to disrupt peace and normalcy," Abdullah posted on Twitter.
He said Jammu and Kashmir police and army were responding to the attack in Uri.
"Militants have struck an army camp in North Kashmir between Baramulla and Uri. Security force casualties are feared. It's an ongoing encounter," he added.
The attack comes just four days ahead of assembly elections in Uri and six other constituencies of the Baramulla district on December 9.
On December 2, the army had foiled an infiltration bid in Handwara area of Kupwara district killing six militants. One army personnel was also killed.
The infiltration bid was foiled as people in Kupwara district were voting to elect their representatives.
