Past financial crises are haunting South Korean policymakers as they rush to support a local credit market that’s quickly gone from one of the world’s safest to teetering on the brink.

As South Korea gets swept into a global debt market rout, corporate treasurers and market regulators in Seoul are staring down one of the most rapid deteriorations in the nation’s credit market ever. The rout is one of the worst in Asia’s local-currency markets amid a broader fixed-income slump this year.

Yields on top-rated five-year South Korean corporate debt have spiked 157 basis points in the three months through October, the worst such blowout on record. One particularly alarming development has been yields surging to a 13-year high on local commercial paper, which companies use to raise funds for short-term payments like payroll.