Light curves of GRB 160625B. From top to bottom: Band 1 (10 – 100 keV), Band 2 (150 keV – 500 keV), Band 3 (500 keV – 1 MeV), and Band 4 (30 MeV – 100 MeV) background-subtracted light curves, binned at 0.1 s. The time interval adopted for the cross-correlation is [185.0, 215.0] s, which accounts for the presence of a burst precursor, with the main emission episode being delayed by ∼185 sec with respect to the trigger time.