  We present a protocol for performing entanglement swapping with intense
pulsed beams. In a first step, the generation of amplitude correlations between
two systems that have never interacted directly is demonstrated. This is
verified in direct detection with electronic modulation of the detected
photocurrents. The measured correlations are better than expected from a
classical reconstruction scheme. In the entanglement swapping process, a
four--partite entangled state is generated. We prove experimentally that the
amplitudes of the four optical modes are quantum correlated 3 dB below shot
noise, which is due to the potential four--party entanglement.
