India is investigating the suspected use of drones by separatist militants after 2 blasts hit an Indian Air Force Station in the northern region of Jammu, two top security officials reported on Sunday.

According to the officials, the blasts in the early hours of Sunday wounded 2 people and caused minor damage to a building. They also said the explosions have caused concern in security circles as they could mark the first time that drones have been used in an attack in the country.

New Delhi has struggled for decades to dampen secessionist sentiments in the disputed Himalayan region of Jammu and Kashmir, blaming neighboring Pakistan for backing insurgencies there.

On Thursday, Indian PM Narendra Modi told leaders from Jammu and Kashmir that elections would be held there once constituencies in the region have been reconfigured following the revocation two years ago of the region’s semi-autonomous statehood.

A senior government official in New Delhi pointed out that Indian Defense Minister Rajnath Singh is expected to review the security situation and that the latest explosions are being investigated.

In a Twitter post on Sunday, the Indian Air Force said “investigations are in progress along with civil agencies,” noting that one explosion caused minor damage to the roof of a building at the station, while the other exploded in an open area.

“There was no damage to any equipment,” it added.

Separately, a top security officer told Reuters that the suspected use of drones in the attack, if established, would present a major challenge for security forces in the area.