  For the class of stochastic partial differential equations studied in
[Conus-Dalang,2008], we prove the existence of density of the probability law
of the solution at a given point $(t,x)$, and that the density belongs to some
Besov space. The proof relies on the method developed in [Debussche-Romito,
2014]. The result can be applied to the solution of the stochastic wave
equation with multiplicative noise, Lipschitz coefficients and any spatial
dimension $d\ge 1$, and also to the heat equation. This provides an extension
of the results proved in [Sanz-Sol\'e and S\"u\ss, 2013].
