Since 1989 ( when Malaysia minted the first RM1 coins and till 1996, fake coins of the RM1 were discovered to be circulating rampantly in the market and many users were caught unaware. Even the BNM (Central Bank Of Malaysia) did not say anything about it. The denied there is an existing fake RM1 coins. The public only realised the fake when police were kept busy catching people doing fake coins. However, BNM withdrew these coins circulation in 1997. The BNM's reason? " BNM further said the withdrawal of the RM1 coins was due to the low demand and increasingly unpopular usage of RM1 coins for purchases of goods and services in Malaysia, unlike those reported by a local daily , which claimed that about 50 % of the 34 millions RM1 coins circulated are fake"... Surprisingly, The Malaysia Royal Mint closed down later in the 2000's due to losses in operation. I can even tell you that since Royal Mint started minting, even the 50 sen Malaysian coins which have fake from 1989 to 2009.
Nowaday, these fake coins are popular with collectors in educating themselves to identify how fake coins look like. " Rings of Fire", "Weak Strike", "Off centred strike", "thinner or thicker planchets" and so on.
I believe that the same mould used by syndicates were the same one used by the Royal Mints. So, how do these mould ended up there, your guess is as good as mine. Funny also, these syndicates did not do any fakes in the years when certain year coins were not minted by the Royal Mint.
I listed here some images of these fake coins known to exist. I just take the year 1993 RM1 ( there were 2 varieties for the year):-