Longest range ballistic missile to have carried conventional Warhead?

By “carried”, I mean actually deployed in the field with a warhead.

Most longer range (for our purposes more than 500 KM) range missile seem to me to have been deployed only with nuclear warheads (and maybe chemical ones for Iraq/Iran/NK). Conventional warheads seem to only be restricted to shorter range ones, indeed that is one of the reasons why short range missile are problematic in arms control, a short range BM has actual non nuclear/WMD uses while I cannot think of anyone arguing that an ICBM is for conventional strike and being believed.

Obviously, using a rocket capable of traveling on a flight into space to carry a bomb somewhere is a pretty expensive way to do it.

I’ve had the impression that the scheme to use ICBMs for conventional strikes is just a scheme to enrich a few defense contractors. The ability to blow anything up, anywhere, within 40 minutes or so at the touch of a button must be really appealing to generals for some reason. And, if the government pays tens of millions of dollars a missile, it obvious appeals greatly to the companies that build them.

It’s of course a horrible idea. The russians and everyone else, if they see a ballistic missile launch, cannot tell from the outside if the missile has a nuke or just a several thousand pound bomb.

Were any ICBM or IRBM ever deployed with conventional warheads?