Image via avherald.com

The Aviation Herald reports that yesterday (5 January 2017), a Boeing 737 operated by LAM - Mozambique Airlines collided with a remotely piloted aircraft while on approach to Tete, Mozambique. The flight crew heard a loud bang and suspected a bird strike, but landed safely and normally.

I think this is the first confirmed case of a drone colliding with an airliner, but please let me know if it has happened in the past.