Auxiliary verb, Ichidan verb, See 迷惑の受身・めいわくのうけみ, ~れる connects to -nai stem of 五段 verbs and to サ変 as さ~れる; ~られる connects to -nai stem of 一段 and カ変 verbs and to サ変 as せ~られる
1. indicates passive voice (incl. the "suffering passive")
See 可能動詞・かのうどうし, no imperative form, not used on 五段 in modern speech