They are one of a growing number of elderly victims believed to be targeted at supermarkets across Auckland.
Police say about $10,000 has been taken from bank accounts after one of the group spies on the victims at checkouts and notes their Pin numbers, then follows them to their car or their home and distracts them while another steals their wallet or bank card.
One couple in their 70s went grocery shopping at Sylvia Park Pak'n Save on Saturday and were unwittingly targeted.
Police believe that someone watched the man enter his Pin, then followed the couple home and waited until they had gone to bed. The thieves broke in and stole the cards as the couple slept.
The man has hearing difficulties and his wife was sleeping deeply so neither heard a sound.
"They took the entire shirt. The cards were in the pocket, it was the same one he was wearing at the supermarket, it was on a chair in the bedroom," the woman told the Weekend Herald.
"The first we knew about it was when the bank phoned us the next morning. It was so freaky."
The thieves had withdrawn $800 just before midnight on Saturday and a similar amount on Sunday morning.
"It's terrifying," said the woman, who did not want her name published in case the thieves recognised her.
"They came in in the middle of the night. It's very traumatising.
"It's horrible, I went to pieces the next day. I just started howling my eyes out."
Detective Senior Sergeant Stan Brown said five women aged 71 to 86 had been ripped off by three offenders.
Mr Brown said one of the alleged thieves, a woman in her 20s, stood behind the victim at the checkout.
"As the elderly woman enters her Pin number, the offender is watching and either filming it with her own cellphone, or making a note of the victim's Pin number into the cellphone."
The victim is then followed home and distracted by a man knocking on the door asking them to come out of the house and check for a missing car, or to investigate a strange noise. Then a second man enters the house and steals the victim's wallet or bag.
Coralie Lush's 86-year-old mother was approached by the alleged offenders at the carpark of Countdown in Milford.
She said the pensioner had a heart attack and was rushed to hospital when she realised her wallet was missing.
"It was a real deliberate, manipulative and very, very cold and calculated theft," said Ms Lush. "Mum's not handling this very well."