We report on a numerical reinvestigation of the Aoki phase in lattice QCD with two flavors of Wilson fermions where the parity-flavor symmetry is spontaneously broken. For this purpose an explicitly symmetry-breaking source term $hbar{psi} i gamma_{5} tau^{3}psi$ was added to the fermion action. The order parameter $<bar{psi} i gamma_{5}tau^{3}psi>$ was computed with the Hybrid Monte Carlo algorithm at several values of $(beta,kappa,h)$ on lattices of sizes $4^4$ to $12^4$ and extrapolated to $h=0$. The existence of a parity-flavor breaking phase can be confirmed at $beta=4.0$ and 4.3, while we do not find parity-flavor breaking at $beta=4.6$ and 5.0.
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