It has traditionally been accepted that quasars and strong emission-line radio galaxies, although situated in regions of enhanced galaxy density, are rarely found within rich clusters (Yee and Green 1984; Longair and Seldner 1978). The recent finding by Yee and Green (1987) that at z ≳0.5 a substantial fraction of optically bright radio-loud quasars are found in galaxy clusters as rich as Abell class 1, suggests that a substantial evolution of the environments of rich clusters has taken place over this short time period. Similar results for radio galaxies have also been obtained by Hill and Lilly (1988, private communication). If this is an evolutionary effect, then at least some first-rank elliptical galaxies in low-redshift rich clusters must contain remnants of active galactic nuclei (AGN). Motivated by this, we attempted to find traces of AGN-like activity in a sample of FR class I radio galaxies which are known to be “quiescent” absorption-line systems situated in low-redshift clusters.