get tough on, take severe/stern measures against, clamp down on, come down heavily on;

eliminate, abolish, eradicate, extinguish, quench, repress, stifle, suppress, put an end to, put a stop to, end, finish, get rid of, crush, put down, weed out, curb, nip in the bud, thwart, frustrate, scotch, squash, quash, quell, subdue, terminate, beat, overcome, defeat, rout, destroy, demolish, annihilate, wipe out, extirpate;

limit, restrain, restrict, check, keep in check, control, keep under control

informal come down on like a ton of bricks, squelch, put the kibosh on, clobber