The woman, identified as Ruby, alleged that Kavi Nagar police did not probe the murder case of her brother Rajendra (20) who was found on railway track two years ago.
She allegedly tried to immolate herself by pouring kerosene oil on her body when the officials were listening to public problems during Tehsil Divas, SHO Ashok Shishodia said.
At the time of the incident Ruby's two brothers stated that Rajendra was run over by train that is why the case remained unsolved, he said.
In a separate incident, a 35-year-old woman identified as Neelam, committed suicide by hanging herself with a ceiling fan in Vasundhara colony here today.
Kiran Pal Singh, her husband informed Indira Puram Police. No suicide note has been recovered, he said.
Police is trying to ascertain the cause of her death, he said, adding the body has been sent for postmortem.