Help ID Shark-like Fish accompanying Mantas in RajaAmpat

[oceanicmanta]

Pls can anyone identify this fish ?
Was diving in RajaAmpat and there were 2 of them accompanying mantas around a cleaning station and kept coming close to check me out.
They are shark-like, with distinct dorsal fins, very fast swimming, huge eyes and look fierce.
I kept turning around to fend them off with my fins and camera flash. According to the instructor on the dive, they are commonly seen in RA following mantas and harmless.

View image: IMG 3656

http://s11.postimg.org/k5rizja7z/IMG_3659.jpg

 

[dumpsterDiver]

Those are cobia. Excellent eating and very strong and difficult to kill..

 

[agilis]

Cobia are closely related to Remoras and, though much larger and predatory, share some of the Remora's scavenger habits, often following larger sea creatures. A juvenile Cobia is almost a dead ringer for a Remora, even having a slightly flattened head.