We present evidence for the first observation of electromagnetically bound $pi^pm K^mp$-pairs ($pi K$-atoms) with the DIRAC experiment at the CERN-PS. The $pi K$-atoms are produced by the 24 GeV/c proton beam in a thin Pt-target and the $pi^pm$ and $K^mp$-mesons from the atom dissociation are analyzed in a two-arm magnetic spectrometer. The observed enhancement at low relative momentum corresponds to the production of 173 $pm$ 54 $pi K$-atoms. The mean life of $pi K$-atoms is related to the s-wave $pi K$-scattering lengths, the measurement of which is the goal of the experiment. From these first data we derive a lower limit for the mean life of 0.8 fs at 90% confidence level.
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