PATNA, Aug. 3 -- A 19-year-old man has been arrested for killing a 14-year-old girl and her 12-year-old brother at their home in Nagwan village on the outskirts of Patna on Thursday afternoon, allegedly after she refused to continue a relationship with him, police said. The girl and her younger brother had returned from school shortly before the incident, which took place between 12:30 and 1.30pm. According to police, the girl was allegedly strangled while her brother was bludgeoned with a brick. Both were then set on fire inside the house. Investigations revealed that the main accused, Subham alias Sunny Kumar, was enraged over the girl's decision to end their relationship. Upset by the breakup and the fact that the girl had stopped speaking to him, he allegedly plotted and executed the gruesome double murder. On Sunday, Patna police claimed to have cracked the case within 24 hours of the incident with the arrest of two accused-Subham and Roushan Kumar, both residents of Phuliatola under Phulwarisharif police station. Police recovered three mobile phones and an empty bottle of kerosene oil from their possession. Patna Senior Superintendent of Police (SSP) Kartikey K Sharma said the case was solved with the help of forensic evidence, dog squad, and CCTV footage. Taking serious note of the crime, the SSP had constituted a Special Investigation Team (SIT) under the supervision of City SP (West) Bhanu Pratap Singh, along with SDPO-2 Deepak Kumar, who collected crucial evidence and tracked the accused to their hideouts. According to the SSP, Subham had purchased kerosene oil from a shop in Khagaul on the day of the incident. He went to the victims' house alone and knocked on the door. The girl opened the door, allowing him to enter. At that time, her brother was asleep. Subham first attacked the brother with a brick, then assaulted the girl and strangled her. Before fleeing, he poured kerosene over their bodies and set them on fire. He then locked the door from outside and fled the scene. SSP Sharma said Subham and Roushan had planned the murder in advance. While Subham carried out the killing, Roushan helped destroy evidence. Police are also questioning the shopkeeper who sold them the kerosene. The accused lived within 3 to 4 km away from the victims' house and had been planning the murder for about a week. Subham used to frequent the girl's house, and Roushan had introduced him to her as they were classmates. Police said Subham suspected the girl of being in a relationship with another boy, which intensified after they stopped talking. Preliminary investigation revealed that Subham and the girl had been friends since their school days and were in a relationship. However, their families disapproved, leading to the breakup. Incidentally, Subham's mother and the girl's mother both work at AIIMS, Patna. The murders came to light when the children's mother returned home and found them dead and severely burnt. Clothes tied around their mouths suggested they were gagged before being set ablaze....