Colombian soldiers defending a state-owned oil pumping station near the border with Venezuela were under attack. Two powerful insurgent groups that have been fighting the Colombian state for decades had been regularly stealing fuel from it. The soldiers were used to snipers and ambushes, but now they had to contend with a new weapon their adversaries have by the thousands: swarms of small drones, the kind hobbyists can buy on Amazon, fitted with clawlike hooks carrying grenades. Over 15 days, the soldiers shot down 50 of them, according to four government security officials familiar with the operation. On the 16th day, a much larger drone, commonly used for spraying pesticides, appeared carrying four grenades. The battalion did not detect it in time. The grenades exploded, killing one soldier, the officials said.

Full report : Security officials say easy access by guerrilla groups to commercial drones, cheaply modified into deadly weapons, has put the nation’s army on its heels.