OXFAM last night said it had suspended all operations with a call centre after claims it was harassing the aged and vulnerable into donating money.

The Cowley-based charity said it had suspended operations with Listen Ltd and Street Academy, which employs so-called “charity muggers” to ask people in the street for donations, pending their investigation.

The organisation was responding to an investigation by the Mail on Sunday, which sent an undercover reporter to train with Listen Ltd who said he was told to target “98-year-old women”, and “new mothers just home from the hospital”.

Oxfam director of fundraising Tim Hunter said: “Our supporters’ generosity is the life-blood of our organisation and we thank the Mail on Sunday for bringing these allegations to our attention.

“However, the headline in the Mail on Sunday claiming that we target 98-year-olds is factually incorrect. It is against our policy to target vulnerable people.

“We take the allegations contained in the article very seriously and have suspended all operations with both Listen Ltd and Street Academy, pending a thorough investigation.”

He said anyone with complaints about the charity’s fundraising methods should email feedback@oxfam.org.uk