During the course of our deep optical imaging survey for Ly \alpha emitters at z \approx 5.7 in the field around the z = 5.74 quasar SDSSp J104433.04-012502.2 , we have found a candidate strong emission-line source .
Follow-up optical spectroscopy shows that the emission line profile of this object is asymmetric , showing excess red-wing emission .
These properties are consistent with an identification of Ly \alpha emission at a redshift of z = 5.687 \pm 0.002 .
The observed broad line width , \Delta v _ { FWHM } \simeq 340 km s ^ { -1 } and excess red-wing emission also suggest that this object hosts a galactic superwind .