Teens arrested after setting Good Samaritan's couch on fire

Two teenagers have been arrested in connection with arson inside an elderly woman's home on Wednesday morning.

An 18-year-old male and 14-year-old female were arrested on Wednesday afternoon, following the attack.

The victim, whose couch was deliberately set on fire after offering four teenagers a glass of water, says she's praying for the perpetrators.

"I'm not long for this world, but these kids desperately need help," she told NZME.

"I've asked my church and everyone I know to pray that the police will catch these children, and they will get the care that they deserve."

Four teenagers knocked on the 88-year-old's door in Ranui, west Auckland, asking for water at 10pm on Sunday, police say.

When she asked them to leave, after they came back a second time, two of them reacted by smashing her windows.

The victim put a couch up against the broken window to secure it overnight.

Later, after going to bed, she was woken by a smoke alarm and found her couch fully ablaze.

Police searched for the four teens - three female and one male - all estimated to be between 14 and 18.

The woman was not injured in the blaze and told NZME she's had a lot of support from neighbours, even ones she didn't know before the incident.

"It just goes to prove there are a lot of good people in this world."

Detective Senior Sergeant Roger Small says: "This is an absolutely appalling crime.

"An innocent elderly victim was targeted in her own home, a place where she should have been able to be safe and feel safe.

"We want to remind our elderly community that they can call us, if they are in a situation where they feel unsafe.

"Often, our elderly community feel like they may be wasting police time or being a bother by ringing us, but we are here for them when they need us and we encourage them not to hesitate to call us."

Anyone with information is asked to call Waitakere Police Station (09) 839 0600 or anonymously on Crimestoppers 0800 555 111.

The police can also be contacted via message on Facebook.