  On December 19, 2002, during the Performance and Verification Phase of
INTEGRAL, a Gamma-Ray Burst (GRB) has been detected and localized in real time
with the INTEGRAL Burst Alert System (IBAS). Here we present the results
obtained with the IBIS and SPI instruments. The burst had a time profile with a
single peak lasting about 6 s. The peak spectrum can be described by a single
power law with photon index $\Gamma$=1.6$\pm$0.1 and flux $\sim$3.7 photons
cm$^{-2}$ s$^{-1}$ (20 - 200 keV). The fluence in the same energy range is
9$\times10^{-7}$ erg cm$^{-2}$. Time resolved spectroscopy performed with
IBIS/ISGRI shows a clear hard to soft evolution of the spectrum.
