Premakumari, from Chikmagalur and a mother of two children, secured a government job on compassionate grounds after her husband, a police constable, died over six years ago.
"He (Ramdas) threatened to commit suicide if I spoke to the media and revealed our conversations, which I had recorded on my mobile handset," she told reporters Tuesday.
Premakumari said she met Ramdas, who was the medical education minister in the first BJP government (2008-13), first in 2009 while seeking a transfer to the deputy commissioner's office in Mysore from Chikmagalur for her children's education.
"I had to resign from the job when I was transferred to Tumkur from Mysore at the behest of Ramdas, who promised to marry me and settle with him," Premakumari said.
Ramdas's family members, however, rubbished Premakumari's charges and accused her of blackmailing him for monetary gain.
