NEW DELHI: Suspected Islamist gunmen attacked an Indian Air Force (IAF) base near the border with Pakistan early Saturday, security officials said, with at least two of the militants and just as many IAF personnel killed.

H S Dhillon, Additional Director General of Police, Punjab, told AFP the operation at the base was still ongoing at 04.15 GMT.

“We are searching the area. Two of the attackers were killed in the initial exchange of gunfire but we can't confirm if more have been killed,” he said, in response to reports that four gunmen had been killed.

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“Five to six security personnel were injured and they have been evacuated to hospital."

Local television stations showed images of helicopters surveying the area, while elite National Security Guard commandos have been flown in to flush out the attackers.

A top security official, who asked not to be named, told AFP that the gunmen were believed to be from the Jaish-i-Mohammad group, describing them as suicide attackers who breached security at the base in the northern state of Punjab while wearing army uniforms.

Kunwar Vijay Partap Singh, director general of police in Punjab's Pathankot district, told AFP that the attack began around 3.30am and that there were four to five attackers.

He said the operation to eliminate the gunmen had lasted three hours. The airbase was being combed to determine the fate of the remaining attackers.

Singh added that there had been no damage to fighter planes at the base and that security forces were still trying to identify the attackers.

One Indian home ministry official said Punjab and Jammu states were on high alert and all defence bases had been sealed.

“Attacking an air base is a serious security threat. The new strategy of the terrorists is to identify defence bases near the border and launch attacks,” said the official, who was not authorised to comment on the record.

Pathankot is on the highway that connects India's insurgency wracked Jammu and Kashmir state with the rest of the country. It's also very close to India's border with Pakistan.

Top security officials including India's National Security Adviser Ajit Doval held a meeting in New Delhi in the aftermath of Saturday's attack, media reports said.

High alert

Authorities had put the state on high alert on Friday after five gunmen in army fatigues hijacked a car driven by a senior police officer, which was later found abandoned on the Pathankot-Jammu highway.

It was not yet clear if there was any link with Saturday's attack.

In July, three gunmen dressed in army uniforms opened fire on a bus and then attacked a police station in the nearby Gurdaspur district of Punjab, killing seven people including four policemen.

While insurgents frequently target police in the volatile Kashmir region, Punjab, a majority-Sikh state, has largely been spared the violence.