Is this a robber or snipe fly?

Is this a robber or snipe fly?

Observation - Is this a robber or snipe fly?. Description: Struggling with this. All help appreciated. Observed on the banks of the Severn Rover, near Welshpool restining on an umbellifer, with a smaller fly clutched in its front legs.

Struggling with this. All help appreciated.
Observed on the banks of the Severn Rover, near Welshpool restining on an umbellifer, with a smaller fly clutched in its front legs.