SNP MP Natalie McGarry is at the centre of a police investigation into money that has gone missing from the accounts of Women For Independence (WFI).

The National understands that a five-figure sum between £30,000 and £40,000, made up of donations by supporters of the group, cannot be accounted for.

McGarry, one of the founders of WFI, had access to a PayPal account used by the organisation to collect donations.

Concerns were first raised with the Glasgow MP months ago, and, according to WFI sources, McGarry has never been able to explain fully where the money has gone.

Last night McGarry insisted she was certain there “had been no wrongdoing on her part.”

It is understood the money first started disappearing during the referendum campaign, and this continued until WFI was first formally constituted as an organisation in March.

The WFI’s National Committee called in the police on Sunday.

In an email sent to members on Sunday evening, signed by all members of the National Committee bar McGarry, the organisation said that its “trust may have been abused”.

It continued: “Following concerns being raised, and painstaking efforts to ensure we have gathered extensive and accurate information, we have been placed in the position of having no choice but to ask the police to help us.

“We have passed the information we have been able to gather to the police and as a result there is now a live investigation. We know you will understand that, in the interest of due process and justice, that limits what we can say.

“But what we can say is that following our first AGM in March and the adoption of our constitution and robust and appropriate systems, concerns emerged in late summer regarding financial probity. For several weeks now we have been examining the finances of the organisation for the last financial year, 2014-15.

“We have identified an apparent discrepancy between our donation income and the expenditure which we currently have evidence of. We have exhausted all opportunities of obtaining adequate evidence or explanation to account for this discrepancy.”

In a statement to press, the organisation went on to say: “Women for Independence has been and is supported by hundreds of women and men who have donated to our work. We know that those people will share our profound disappointment that this situation has arisen.

“The situation we have referred to the police for further inquiry is serious but we want to stress to our supporters that appropriate, robust and transparent controls are now in place to protect any monies donated to WFI.”

McGarry’s campaign was one of the most high-profile of the General Election. The 34-year-old overturned then-shadow Scottish secretary Margaret Curran’s 11,840 majority. She is currently the SNP’s spokeswoman on disabilities.

A spokeswoman for Police Scotland said: “We can confirm that a report has been received by Police Scotland. An investigation is now under way.”

A party spokeswoman said: “The SNP are aware of reported discrepancies in the accounts of Women for Independence however we have yet to see the detail behind these claims.”

McGarry did not respond to The National’s request for a comment.

Late last night, solicitor Aamer Anwar issued a statement on behalf of the politician.

It said: “Natalie McGarry MP is aware that suggestions of reported discrepancies in the accounts of Women for Independence have been passed to Police Scotland. This morning I contacted Police Scotland at Natalie’s request to advise them that she is ready to meet with them should they wish to.

“Accordingly I have advised Natalie that it would be inappropriate to make any further comment until the conclusion of that inquiry, other than to state that she is certain that there has been no wrongdoing on her part.”