A 15-year-old boy arrested on suspicion of murdering an elderly couple, who were killed in a Warwickshire house fire, has remained in custody after detectives were granted more time to quiz him.
Kath and Albert Adams, both 77, died after a mobility scooter parked outside their home in Rugby was torched and the blaze spread to their sheltered housing complex.
The teenager, also from Rugby, was arrested on Tuesday and is also suspected of arson with intent to endanger life after two fires at the block, Warwickshire Police said.
Mr and Mrs Adams died after fire swept through their home on Saturday.
In a statement issued by Warwickshire Police, family members including son Keith and daughter Nicola described the couple as "a lot of things to a lot of people".
They added: "They were really loved by their family and were the rock that pulled everyone together.
"Their tragic deaths have left a massive hole in our lives - that pain will never truly fade."
Police said the fatal fire is being connected to a second one at the same flats on Monday morning, which also involved a mobility scooter but left nobody injured.