Two Hong Kong lovers were arrested on Friday after their early morning row resulted in a fire ripping through a public housing estate flat, leaving one man dead and one woman in a coma. The female tenant, 48, and her boyfriend, 39, were detained on suspicion of arson about five hours after the 12th-floor blaze at Pak Tin Estate in Shek Kip Mei was first reported to emergency services at 2.21am. A police source said officers had been called in to mediate a dispute between the woman and her boyfriend on a street nearby about three hours before the fatal fire. He said the pair were given a verbal warning and allowed to leave, adding that police were now investigating whether the duo, who had a history of drug use, were on substances at the time of the quarrel in the Pak Tin Estate flat. More than 900 residents were evacuated from Block 13 of the estate, while 12 people, including two children, were sent to Princess Margaret Hospital and Caritas Medical Centre to be treated for various minor injuries, including smoke inhalation. One of the woman’s neighbours, a 34-year-old man who lived on the same floor, fell to his death when he climbed out the window in an effort to escape, police said. “Dense smoke poured out from the burning unit and spread into his flat. As he tried to climb onto the clothes-drying rack outside the window to escape, he lost his balance and fell off the building,” Superintendent Lui Che-ho said. The man suffered multiple fractures and was taken to the medical centre, where he was certified dead. A dozen other victims, six men and six women, aged between five and 83, were sent to hospital for treatment. One of the women, who was unconscious, was taken to Princess Margaret Hospital and was in critical condition, officials said. Police believe the fire started when a cigarette was thrown in the flat. “We are still exploring why the fire eventually turned into such a disaster,” Lui said, adding that government experts would help identify the cause of the blaze and why it spread so unusually. No accelerant was found at the scene, police said. The superintendent said the two suspects were believed to have regularly argued about their relationship. They did so again on Friday, and left the flat before the fire got out of control, he said. They were arrested at the man’s flat nearby and were both unhurt. 103-year-old woman and son, 59, found dead in Hong Kong flat Yu Wai-ming, an assistant divisional officer with the Fire Services Department, said there were “no major difficulties in fighting the fire … but there were quite a number of requests for assistance”. Officers used one water jet and mobilised one breathing apparatus team to fight the blaze, which was extinguished at 3.12am, he said. His colleague, Kowloon West divisional officer Iu Pun-yan, said the department considered the fire to be suspicious because of the unusual way the flames spread. As of Friday evening, the two suspects were still being held for questioning and had not been charged.