Mechanisms of the combustion of ammonia NH3 (g) in oxygen O2(g)

[Jon83]

Hello everyone!
I am told that under normal temperature and pressure conditions ammonia NH₃(g) burns in the presence of oxygen to give nitrogen N₂(g) and water H₂O.
But I want to understand the exact mechanism of this reaction and how the molecular orbitals of each reactant are transformed to give the products? And how do the electrons circulate?