Chris Harper Mercer, the man identified as the gunman in the killings at Umpqua Community College in Roseburg, Oregon, on Thursday, was a withdrawn young man who neighbours said wore the same outfit every day - combat boots, green Army pants and a white T-shirt - and was close to his mother, who fiercely protected him.
Neighbours in Winchester, Oregon, and Torrance, California, where Mercer (26), lived with his mother, Laurel Harper, remembered a reclusive and seemingly fragile young man with a shaved head and dark glasses who seemed to recoil from social interaction.
"He always seemed anxious," said Rosario Lucumi (51), who rode the same bus in Torrance as Mercer when she went to work.
She said she believed he took it to El Camino College. “He always had earphones in, listening to music,” she said.
"He and his mother were really close," said Ms Lucumi, who estimated that Mercer and his mother, who shared a small one-bedroom apartment in Torrance, had lived there for less than a year. "They were always together."
Mercer appeared to have sought community on the internet. A picture of him holding a rifle appeared on a MySpace page with a post expressing a deep interest in the IRA.
It included footage from the conflict in Northern Ireland set to The Men Behind the Wire, an Irish republican song, and several pictures of gunmen in black balaclavas.
In the offline world, Mercer’s mother sought to protect him from all kinds of neighbourhood annoyances, former neighbours in Torrance said, from loud children and barking dogs to household pests.
Once, neighbours said, she went door-to-door with a petition to get the landlord to exterminate cockroaches in her apartment, saying they bothered her son.
Mercer and his mother shared an apartment in Winchester, a dun-coloured building that sat roped off behind police tape Thursday, guarded by sheriff’s deputies who shooed away reporters.
Bronte Hart, a neighbour who said she lived in an apartment below Mercer’s, described a more assertive young man than his former neighbours in California did. Far from avoiding social interaction, she said, he frequently shouted at her for smoking on her balcony.
"He yelled at us, me and my husband," said Ms Hart, who lives in the building with her husband and father. "He was not a friendly type of guy. He did not want anything to do with anyone."
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