We report on low-resolution multi-object spectroscopy of 30 faint targets (
R similar or equal to 24-25) in the HDF-S and AXAF deep field obtained with
the VLT Focal Reducer/low dispersion Spectrograph (FORS1). Eight high-reds
hift galaxies with 2.75 < z < 4 have been identified. The spectroscopic red
shifts are in good agreement with the photometric ones with a dispersion si
gma(z) = 0.07 at z < 2 and sigma(z) = 0.16 at z > 2. The inferred star form
ation rates of the individual objects are moderate, ranging from a few to a
few tens M. yr(-1). Five out of the eight high-z objects do not show promi
nent emission lines. One object has a spectrum typical of an AGN. In the AX
AF field two relatively close pairs of galaxies have been identified, with
separations of 8.7 and 3.1 proper Mpc and mean redshifts of 3.11 and 3.93,
respectively.