  In the present paper it is proved that every inner 2-local derivation on the
matrix ring $M_n(\Re)$ of $n\times n$ matrices over a commutative associative
ring $\Re$ is an inner derivation. Also, it is proved that, every derivation on
an associative ring $\Re$ has an extension to a derivation on the matrix ring
$M_n(\Re)$ of $n\times n$ matrices over $\Re$.
