On special congruence subgroups of symplectic groups

In this paper, it is proved that every special congruence subgroup $SSp(V,I)$ of the symplectic group $Sp(V(R))$, where $R$ is a ring of stable rank $1$ with invertible element $2$ and $\dim V(R)\ge 4$, is generated by the symplectic transvections belonging to this subgroup. This result is used to obtain the complete description of the normal subgroups of $Sp(V(R))$.