Nearly one-fifth of killings reported in the national capital this year could be attributed to fights over trivial issues, such as an accidental brushing-of-shoulder or inability to serve cold water, making them second most common cause of fatal incidents here, according to police data. Experts believe that sedentary lifestyle, emotional instability and poor social communication maybe reason behind spurt in such cases. According to a recent Delhi Police data, 62 of the 337 killings (or 18.39 per cent) reported till September 15 this year in Delhi took place due to sudden provocation over trivial issues. According to the data, personal enmity continues to remain as the most common motive behind murders. During the last two years, too, personal animosity occupied the top place, followed by violence over sudden provocations or trivial issues. As per the Delhi police data, 93 out of the 487 cases reported last year were related to sudden provocation. 421 of these reported cases were worked out, the police data shows. In 2016, 88 out of the 528 killings reported were due to sudden provocation. Out of the 528 murder cases registered, 409 were solved. Out of the 337 killings reported till September 15 this year, 65 were over personal enmity and 44 cases were due to family dispute. In September, a man was beaten to death allegedly by his former employer after he refused to fill water for him from the tanker in outer Delhi's Ranhola area. In August, a 26-year-old man was beaten to death by another man after an altercation over the victim's shoulder touching his while they were crossing a road in outer Delhi's Nangloi. In another incident, A 26-year-old man was stabbed to death by three persons including a juvenile following an argument over Rs 500 which he had lent to one of the accused in east Delhi's Kalyanpuri. "Very small issues are triggering fights between people leading to bloodshed. Recently, there was a case where a helper of a bus killed the driver after the latter refused to return his phone which he had borrowed in northwest Delhi," said an investigative officer. The officer feels that pressure of the day-to-day life and growing materialism are also the reason behind such incidents. In July, a 20-year-old man was stabbed to death in front of his wife by one of his friends following a quarrel over serving cold water. Sudden provocation over trivial issues often lead to sudden anger outburst and sometimes killings, an AIIMS doctor said. "Such a behaviour of a person could be based on multiple factors including sedentary lifestyle, poor social communication, maladjustment with changing socioeconomic situations in family, use of alcohol and drugs, underlying depression, emotionally unstable brain and poor dietary intake," said Dr Nand Kumar, Physiatrist, AIIMS said. "In most of the cases, poor mental health leads to poor decision-making capacity and also contributes to sudden provocation, whereas in some cases, anti-social personality trait, depression, paranoia can also result in abrupt and sudden action which could lead to violence," he added.