The woman said she had also gone to the 5, Kalidas Marg residence of Chief Minister Yogi Adityanath to raise the matter, but no one there heard her.
She then tried to immolate herself in front of the state assembly building, facing the Bharatiya Janata Party (BJP) state headquarters.
The police officers there immediately rushed in and stopped the teacher from immolating herself. She had already doused herself with kerosene and was striking a matchstick when some women police personnel overpowered her.
The woman said she teaches at Saraswati Shishu Mandir School and the principal Vinod Awasthi had molested her. She alleged he had been torturing her ever since she told him that she would file a complaint with the police and make the matter public.
She also accused the police of sitting on her complaint, and alleged that police officers at Qaiserbagh Chowk police station have been putting pressure on her to "compromise and close the matter".
Earlier this month, Uttar Pradesh BJP lawmaker Kuldeep Singh Sengar was arrested on charges of raping a 15-year-old girl in Unnao. The saffron-robed Chief Minister Yogi Adityanath was accused of going soft on the lawmaker in the Unnao case.
The case came into the media glare when earlier this month, the girl tried to kill herself in front of Mr Adityanath's house in Lucknow.
With inputs from IANS
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