A jobless ex-convict who shot himself dead yesterday 12 hours after allegedly killing a resident of his public housing estate had previously been jailed for wounding another neighbour.
Police were investigating gunman Li Tak-yan's background and looking for any links to Liu Kai-chung, 43, who was fatally shot late on Saturday night. A police source said there was no indication the two men knew each other.
Liu was found in the lift lobby near his home on the 21st floor of Lok Ching House on the Kai Ching Estate in Kowloon Bay. Li, 51, lived 11 floors below.
The shooting sparked a 12-hour drama, which ended when elite police used stun grenades and tear gas to storm Li's flat. They found him fatally wounded with a gun by his side.
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A police source said mental health issues were among the lines of investigation. "At this stage, a mental problem is one of the possibilities, " the source said.
The latest drama began at about 11.20pm on Saturday when residents on the 21st floor heard arguing followed by three gunshots. Liu was shot twice in the chest and once in the back. Three empty 7.62mm cartridges were found at the scene.
The police source said CCTV footage showed Li and Liu taking the lift with other residents. Liu walked out at the 21st floor and Li followed. "CCTV footage showed they did not have any conversation inside the lift," the source said. Li then returned to his flat, where he lived alone. Police cordoned off the building until 5am when residents were allowed back inside.
The police source said the CCTV footage helped to identify Li as the gunman. Police sealed off the 10th floor, phoning residents and ordering them to stay inside as 150 officers surrounded the building.
Shortly before 11am, Li fired two shots at police, who returned a single shot. No one was hurt. Li then clambered onto his flat's window ledge and pointed a gun at his head before returning inside, from where a gunshot was heard at 11.13am. Police then fired more than 20 rounds of tear gas and stun grenades into the flat and two "Flying Tigers" special duty officers slid down ropes and entered. Li was found unconscious with a 7.62mm gun by his side. A second 7.62mm weapon was found later. Li was declared dead at a hospital.
Police are working with Guangdong authorities to trace the guns, as such weapons usually come from the mainland.
Liu, an air-conditioning technician, is survived by his wife in Zhuhai and a son, five, who lives with Liu's sister in Hong Kong. Li's wife also lives on the mainland.
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Correction: An earlier version of this article gave the name of the alleged gunman as Lee Tak-yan, the name released by police on Sunday. On Monday evening, police confirmed that the suspect's name is Li Tak-yan.