  We report a serendipitous discovery of broad absorption lines that were newly
formed in the spectrum of the high-redshift, luminous radio-loud quasar TEX
1726 + 344, in a time interval of only 12 years. This is the first quasar
showing a transition from narrow absorption lines to broad absorption lines. It
also becomes one of the few radio-loud broad absorption line quasars. The gas
cloud responsible for these broad absorption lines is derived to have
parameters coinciding with those of the remnant of a tidally disrupted star.
