Police in India’s northern border state of Punjab have arrested a soldier in connection with last week’s killing of four others at a military base, they said on Monday.

The four were shot dead in their sleep in barracks at the Bathinda military base early on Wednesday.

The killings were suspected to have been motivated by “personal enmity”, district police chief Gulneet Singh Khurana told reporters.

If found guilty, the soldier faces the penalty of expulsion from the army, a court-martial and criminal prosecution in the civilian courts, the last of which could bring a life term or even a capital sentence.

In a statement, the Indian Army said that on interrogation, the soldier had “confessed to his involvement” in stealing an assault rifle and killing four colleagues.

“Initial investigations indicate that this was apparently due to personal reasons or animosity,” it added.

It said the soldier told police he hid the rifle, stolen on April 9, before retrieving it for use in the shooting on April 12, at a time when he was on sentry duty.

Later he threw the weapon into a sewage pit from which it was recovered, the army said, adding that the soldier had tried to divert suspicion from himself by saying he had seen two men flee.

“The Indian Army practices zero tolerance of such acts of indiscipline,” it added, vowing to ensure punishment according to the law.