Reactive dyes of the formula ##STR1## in which R.sub.1, R.sub.2, R.sub.3 and R.sub.4 independently of one another are hydrogen or substituted or unsubstituted C.sub.1 -C.sub.4 alkyl, B is an aliphatic bridge member, Y.sub.1 and Y.sub.2 independently of one another are halogen or carboxypyridinium, A.sub.1 is the radical of an anthraquinone, phthalocyanine, dioxazine, formazan or disazo dye or a radical of the formulae (2a) to (2h) defined in claim 1 and A.sub.2 is as defined above for A.sub.1 or is a radical of the formulae (2i) to (2m), where A.sub.1 and A.sub.2 have different meanings to one another, are particularly suitable for dyeing or printing fibre materials containing hydroxyl groups or containing nitrogen. Dyeings having good fastness properties coupled with a high tinctorial yield are obtained.