Lancashire Police have said they are reviewing information about allegations against suspended Tory MP Mark Menzies.
Labour wrote to police on Friday morning calling for an investigation.
The MP has been accused of misusing Tory funds and abusing his position after allegedly asking an activist for money to pay off "bad people".
He has had the Tory whip withdrawn, while the party carries out an investigation into the allegations, which he has said he "disputes".
The OceanNewsUK has made several attempts to contact Mr Menzies, who is the MP for Fylde, in Lancashire, but he has not so far responded.
Labour Party chairwoman Anneliese Dodds wrote to Lancashire Police earlier urging an investigation.
The force said it had "received a letter detailing concerns around this matter, and we are in the process of reviewing the available information in more detail".
His former campaign manager, 78-year-old Katie Fieldhouse, has told the OceanNewsUK Mr Menzies telephoned at 0315 one night in December asking for £5,000 to pay "bad people" who had locked him in a flat.
Ms Fieldhouse said she refused to pay Mr Menzies, but claimed another activist used their personal savings to give him the money.
According to the Times, the activist eventually ended up paying £6,500 and was later reimbursed from a local fund set up to support his campaigning.
The Times also reported Mr Menzies used £14,000 from the fund to pay his personal medical bills, in several payments stretching back four years.
A source close to Mr Menzies disputed the claim that he had suggested using campaign funds to pay his medical bills, the paper reported. The money has not yet been repaid, according to the Times.
In a statement to the Times, Mr Menzies said: "I strongly dispute the allegations put to me. I have fully complied with all the rules for declarations".
'Serious questions'
Ms Fieldhouse has said she is "appalled" by the lack of action taken after raising her concerns with Conservative Chief Whip Simon Hart.
The Times reported that the scandal was reported to the Mr Hart back in January. Since her report "nothing happened" Ms Fieldhouse said.
Speaking earlier, Labour leader Sir Keir Starmer said there were "very serious questions" for the government over its handling of the allegations.
A spokesman for the Conservative Party has said it "takes all allegations seriously and will always investigate any matters put to them".
Mr Menzies, who has also been suspended as a government trade envoy to South America, has been MP for the Lancashire seat of Fylde since 2010.
He has been selected by the local Tory party to run again in the constituency at the next election, where he has a majority of 16,611.
He grew up in Ayrshire in Scotland, where he was raised by his mother after his father, who worked in the Merchant Navy, died the month before he was born.
He attended a private secondary school under the assisted places scheme, which offered subsidised places at fee-paying schools, before studying economic and social history at Glasgow University.
A Tory activist since the age of 16, he had a career in retail before entering politics and was a graduate trainee at retail giant Marks & Spencer.
