Woman, 28, held over death of grandmother
The 28-year-old has been detained in custody and a report sent to the procurator-fiscal.
Hannah Smith, 63, was found dead on Monday evening at her fourth-floor flat in Cranhill, Glasgow, after police forced entry.
Her granddaughter had alerted police after not being able to contact the widow since Christmas Day.
The victim's brother, James Currie, said he had no idea why his sister was killed.
Mr Currie, 60, said: "She had a few good friends she liked to have a wee drink with, but she had no enemies. I can't believe this has happened.
"She didn't have anything to justify killing her for and I'm under the impression nothing was stolen, so I'm mystified."
Mr Currie told how he waited outside the door of his sister's flat as officers used a battering ram to force it open.
He said police would not let him in because it was a crime scene.
Mrs Smith's neighbour, John Farrell, also said the grandmother rarely ventured outside her flat.
"She hated being outside and couldn't face supermarkets where there would be lots of people," the 75-year-old said. "She would never consider a holiday and would easily spend six months at a time without ever leaving her flat."
Officers have been trying to piece together Mrs Smith's last movements after 7pm on Christmas Eve and have been carrying out door-to-door inquiries at the high-rise block.