Mechanism for reaction of NOCl (Tilden reagent) with primary amines

According to The Pearson Guide To Organic Chemistry For The IIT JEE by Atul Singhal, the reaction between $\ce{NOCl}$ and $\ce{CH3CH2-NH2}$ is as follows:

$$\ce{CH3CH2-NH2 + NOCl -> CH3CH2Cl + N2 + H2O}$$

But how exactly does the reaction proceed?

The first step (what I think) could be that $\ce{NOCl}$ dissociates into $\ce{NO+}$ and $\ce{Cl-}$ ions and then the $\ce{Cl-}$ ion attacks the amine group and replaces it by $\mathrm{S_N2}$ mechanism.

But according to paperplane.io (via the Internet Archive), a diazonium product is produced. Even though a diazo product is formed, how does it produce an alkyl halide according to my textbook?