This is huge, to say the least, but the consensus was that with an approval rating of five percent (!) it had to happen.
National elections will be held within 60 days, and the liberal parties (there are two major ones here) have a lot of momentum on their side. (Park was the leader of the country's conservative party which is in a lot of obvious turmoil now.)
And the big one: Park is now subject to criminal prosecution. She could very likely wind up in jail.