Bose-Einstein correlations of identical charged pions are studied in deep inelastic ep scattering events measured with the ZEUS detector at HERA. In one-dimensional analysis the radius of the particle production source and the correlation strength are independent of the exchanged photon virtuality Q² in the range between 0.1 and 8000 GeV². No significant difference was found between the correlations measured in the target and current region of the Breit frame for Q² > 100 GeV². The result indicates insensitivity of the radius of the source to the underlying hard process. Two-dimensional analysis performed in the Longitudinally CoMoving System indicates an elongated shape of the source.

PACS numbers: 13.90.+i