The Kajra police station house officer has been suspended for negligence leading to the murder of three persons in a Lakhisarai village on Friday.

Ramshekhar Singh (65), Sanjiv alias Jhalo Singh (40), and Ripu Singh (34) were attacked on Friday on the outskirts of Pokhrama village, around 120km east of Patna, over a land dispute.

Lakhisarai superintendent of police (SP) Arvind Thakur on Sunday said Kajra station house officer (SHO) Sanjiv Kumar had been suspended and departmental proceedings initiated against him for negligence of duty.

The police found from the villagers that one of the deceased had lodged a written complaint at the police station a week before the murder, apprehending threat to their lives from their rivals. The people claimed SHO Sanjiv did not act on the complaint against the Kiran Singh and Dharmaraj Singh, the people named in the complaint.

The disciplinary action against the SHO came after a review meeting chaired by deputy inspector-general of Bhagalpur range Vikas Vaibhav in Munger on Saturday. Vaibhav has additional charge of the Munger range.

Officers associated with the probe said DIG Vaibhav was shocked to hear that the incident took place at Pokhrama village even after a written complaint was lodged - family of the deceased have demanded action against Sanjiv.

When SP Thakur visited Pokhrama on Friday, a group of residents had alleged that the SHO had not taken action against Kiran and Dharmaraj. Lakhisarai sub-divisional officer Pankaj Kumar was assigned to probe the allegations against the SHO, and the allegations were found true. He then recommended Sanjiv's suspension for inept handling of the case.

Sources said the SHO was manhandled by a mob when he visited Pokhrama on Friday after the murder.

SP Thakur also said Kiran Singh, the main accused in the murder, has been arrested and raids were on to nab the others involved. Kiran, sources said, is a former member of the Pokhrama panchayat and has political connections. They claimed the police swung into action after Rajiv Ranjan alias Lallan Singh, a senior minister in the Nitish Kumar cabinet, spoke to Thakur on the phone and asked him to take disciplinary action against the officer responsible for the negligence.

Lakhisarai comes under the Munger Lok Sabha constituency, and Lallan - now the minister for water resources and planning and development - had unsuccessfully contested the 2014 Lok Sabha election from the Munger seat. Family of the deceased is considered close to the minister, who is at present in Delhi.

Preliminary investigation revealed that the two rival groups had an altercation in April over six acres of land on the outskirts of Pokhrama village. Though both groups fired at each other, nobody was injured in the firing that time, said a police official.