RJD legislator Saroj Yadav on Thursday threatened to immolate himself if the men who killed his sister three days ago were not arrested soon.

Saroj's sister, Shail Devi (40), was attacked with iron rods on Monday night when she resisted a molestation attempt in a moving autorickshaw. She was admitted to a government hospital in Patna, where she succumbed to her injuries on Tuesday.

The MLA from Bhojpur's Barhara accused the police of being callous from Day 1.

" Agar police abhiyukto ko jald giraftar nahi karti hai to mein atmadah kar lunga. Saath hi, doshi police karmiyon padh bhi karwayee honi chahiye (I will commit self-immolation if the police fail to nab the accused soon. At the same time, action should be taken against the erring cops)," Saroj told The Telegraph over the phone on Thursday, sounding very upset. "The role of the local police is far from satisfactory," said Saroj, adding that he would not hesitate to immolate himself if denied justice.

"I don't have faith in the police but I do have faith in my government. I have demanded strong disciplinary action against the SHO of Chandi police station, Sunil Kumar, and the (former) (Bhojpur) superintendent of police Naveen Chandra Jha."

The new Bhojpur superintendent of police (SP), Kshatraneel Singh, met the MLA and his family soon after assuming charge on Wednesday. The SP said SHO Sunil had been suspended and departmental proceedings had been initiated against him.

"The police will leave no stone unturned to bring culprits to book," SP Singh said.

Two of the five accused, Mithilesh Kumar and Santosh Singh, surrendered before a court in Ara on Wednesday and were remanded in judicial custody at Ara district jail for two weeks. "The three others are still at large. The police conducted raids on their suspected hideouts but in vain," said Reshu Krishna, deputy superintendent of police.

In the FIR lodged at Chandi police station Shail Devi's son, Krishna, said: "My mother told me that the autorickshaw driver and four people inside started misbehaving with her. When she told them that she was the sister of the Barhara MLA, they smashed her head with an iron rod and threw her out - they wanted to kill her to conceal their identity."

The incident gave opposition parties an opportunity to attack the Nitish Kumar government.

"The state government has completely failed on the law and order front," said Dipankar Bhattacharya, national general secretary of CPI-ML (Liberation), at a public meeting in Bhojpur on Thursday.