UPDATE: 5: 07 a.m. EST — Pakistan’s foreign ministry condemned Saturday's attack at the Pathankot Air Force Base in Punjab, India. Authorities are investigating the attack on the Indian air force base near the border with Pakistan, which has been linked to terrorist group Jaish-e-Mohammed.

"Pakistan condemns the terrorist incident in Pathankot, India, today, in which many precious lives have been lost. We extend heartfelt condolences to the Government and people of India and the bereaved families and wish the wounded speedy and full recovery. Pakistan remains committed to partner with India & other regional countries to eradicate the menace of terrorism afflicting our region," the statement said. 

A former Indian Air Force official, who was arrested for allegedly spying for Pakistan, will reportedly be questioned Saturday in connection with the attack in Pathankot, about 300 miles northwest of India’s capital New Delhi.

Four terrorists were reportedly killed during a gunbattle that lasted for more than five hours early Saturday. During combing operations gunshots were heard again at the base, giving rise to concerns that more terrorists may have been holed up inside the air force base. However, sources later said that the surviving terrorists may have escaped, according to NDTV, a local news network.

Original story:

Fresh gunshots were heard Saturday during combing operations following an attack at the Pathankot Air Force Base in Punjab, India, according to local reports. Authorities suspect that three more terrorists may still be holed up at the Indian air force base near the border with Pakistan, according to the Times of India, a local newspaper.

Two loud explosions were heard from within the air force base where a search operation for a fifth suspect was underway, Asian News International (ANI), an Indian news agency, reported. Earlier reports said that at least four heavily armed terrorists entered the base early Saturday that resulted in a gunbattle that went on for more than five hours. Four gunmen and three security personnel we reportedly killed in the exchange.

The attack comes just days after India's Prime Minister Narendra Modi and Pakistani leader Nawaz Sharif met in Lahore in a surprise effort toward peace between the two nations. 

“Sad that this happened after some efforts were made to restore peace with Pakistan,” Punjab Congress chief Amarinder Singh reportedly said.

As authorities investigate the attack, few details about the terrorists emerged. The gunmen had reportedly infiltrated into India three days before the attack Saturday and were suspected to have hailed from Bahawalpur in Pakistan, a source told news agency ANI. Indian intelligence also reportedly traced some phone calls by the terrorists to handlers in Pakistan.

“Pakistan is our neighbor, we want peace, but any terror attack on India will get a befitting response,” India’s Home Minister Rajnath Singh reportedly said.

Authorities suspect that the attack was carried out by Jaish-e-Mohammed, a terrorist group that has its base in Pakistan and is active in the terrorist violence in Jammu and Kashmir. According to reports, a sheet of paper with the name of the group written on it was recovered from a car whose driver was killed at the Pathankot base.

Jaish-e-Mohammed is viewed as the principal terrorist organization in Jammu and Kashmir. The group has been designated as a terrorist organization in several countries, including Australia, Canada, India, the UAE, the U.K. and the U.S.

According to local reports, Maulana Masood Azhar, who formed Jaish-e-Mohammed and was released in Dec. 1999 during a swap for passengers of hijacked Indian Airlines Flight IC 814, was suspected to be behind Saturday's attack.

Jaish-e-Mohammed has also been accused of being involved in the 2001 attack on the Parliament of India in New Delhi that left 14 people dead, including five Jaish-e-Mohammed terrorists.

The state of Punjab was put on maximum alert while security measures were also tightened in neighboring states. India’s Defense Minister Manohar Parrikar is scheduled to hold a high-level meeting with security officials Saturday evening.