Babloo Yadav, son of slain village head Nanhe Yadav who allegedly shot Haq dead using a country-made gun, was apprehended in Pratapgarh district, CBI sources said.
The sources said CBI has detained two brothers of Nanhe Yadav and members of his domestic staff in connection with the DSP's murder and is likely to arrest them soon.
Sources claimed Babloo, who is over 19 years of age, during intense grilling by CBI officials confessed to have shot the police official. The officials were able to reproduce the complete chain of events which took place on March 2, 2013.
Asked about role of UP minister Raghuraj Pratap Singh, alias Raja Bhaiya, in the murders, they claimed the probe in the larger conspiracy is still on.
CBI sources claimed Haq, who was posted as Deputy Superintendent of Police at Kunda, had reached the house of Nanhe Yadav after getting the news of his murder.
By the time he approached the site, the news of Yadav's murder had spread and a large crowd gathered outside his house which was angry at the alleged apathy of the police and protested the police's alleged failure to stop the murder.
At the house of Nanhe Yadav, Haq met a mob which entered into a scuffle with him while his fellow policemen allegedly deserted him, the sources said.
In the crowd was Yadav's brother Suresh who was armed with a rifle. As the scuffle was on, Suresh was killed after his gun accidentally went off, they said.
CBI sources claimed that enraged by the killing of his father and uncle Suresh Yadav, Babloo Yadav, who had a country-made gun, came out of his house and shot Zia-Ul-Haq dead who was being beaten up by a mob.
The sources claimed role of other suspects -- brothers of Nanhe Yadav and his domestic help -- is also under probe and they are being questioned by the agency.
The sources said agency has recovered the weapon, allegedly used in the killing Haq, from Babloo.
The agency has already arrested alleged killers of Yadav -- Ajay Pal and Vijay Pal -- both sons of Kamta Pal who is also a suspect in his murder and is absconding, they said.
The Pal family was having land dispute with Nanhe Yadav's family which resulted in village head's murder, they claimed.
The case was handed over to CBI on a request of slain DSP's wife Parveen Azad who accused Raghuraj Pratap Singh of having a role in the murder of her husband. She had also filed an FIR in this regard naming Raja Bhaiya and his close aides in the murder.
After getting the case, the agency constituted a team of 10 officers led by DIG Anurag Garg and SP Rakesh Rathi to investigate the case.
The team had recently made some important recoveries which included a blood-stained ammunition belt from a box concealed in a house of Suresh Yadav, one of the deceased, a bloodstained wooden rod from another area in the village and service revolver of Haq.
Kunda circle in Pratapgarh district comprises four police stations -- Hathigavan, Manikpur, Kunda and Nawabganj.
CBI has registered four cases pertaining to the three murders in village Balipur, police station Hathigawan in Kunda tehsil which included FIR registered by Haq's wife Azad who had named five persons as accused in the murder of her husband.
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