Samajwadi Party member of Parliament Atiq Ahmed surrendered before an Allahabad court on Saturday for his alleged role in the murder of local Bahujan Samaj Party member of Legislative Assembly Raju Pal.
Pal was gunned down in a sensational shoot-out in Allahabad last month.
Ahmed, an alleged mafia don, is among the key accused in the murder. He has been sent to 14 day's judicial remand in the Naini jail in Allahabad, his hometown, where his name spells terror.
The Lucknow police had arrested Ahmed's younger brother Azim Ashraf, also a key accused in the case, a day after the murder. He is currently in judicial custody.
The murder sparked off state-wide protests and BSP chief Mayawati led a massive demonstration in Lucknow earlier this week to press the party's demand for a Central Bureau of Investigation probe into the matter.
Pal's wife Pooja Pal on Thursday moved a writ petition before the Supreme Court seeking judicial intervention for entrusting the probe to the CBI.
Her counsel and BSP national general secretary Satish Misra urged the apex court to interfere in the matter, as the victim's family had no faith in the Mulayam Singh Yadav government's police machinery, which was investigating the case.
"Since we are strongly of the view that the ruling Samajwadi Party and its leaders are behind the murder conspiracy, how can we expect justice from their own official machinery?" asked Misra.
The BSP has dismissed Ahmed's surrender as an attempt to prevent a CBI probe into the murder.
State BSP chief Barkhu Ram Verma told rediff.com over telephone, "Since the Supreme Court has already issued notices to the state government as well as to Atiq Ahmed and his brother, Mulayam Singh Yadav is scared that his lieutenants' role in the murder would get exposed if the investigation was handed over to CBI."