In the integral cohomology ring of the classifying space of the projective linear group P GLn (over C), we find a collection of p-torsion classes y p,k of degree 2(p k+1 + 1) for any odd prime divisor p of n, and k β₯ 0. If, in addition, p 2 β€ n, there are p-torsion classes Ο p,k of degree p k+1 + 1 in the Chow ring of the classifying stack of P GLn, such that the cycle class map takes Ο p,k to y p,k. We present an application of the above classes regarding Chern subrings.