Essex Police say they are trying to contact a university student who claims she was sexually assaulted by the US rapper Nelly after a gig in Southend.
The unnamed woman's allegation is detailed in a lawsuit brought against the performer by another woman who says she was raped by him.
Legal documents filed in the US say the alleged Essex victim reports she was attacked by Nelly after his gig at The Cliffs Pavillion in December last year.
Nelly, who's real name is Cornell Iral Haynes Jr, denies all the allegations, which his lawyer says are "deceitful" and "motivated by money".
A spokesman for Essex Police said: "We have checked our records and don't appear to have received a report of this incident."
He said that they were working to contact the Seattle-based law firm dealing with the US civil case in an attempt to get more details about the UK assault allegation.
The Washington lawsuit is being brought by student Monique Greene, 22, who says she was raped by Nelly on his tour bus. She contacted police but a criminal case was dropped because she would not testify in court.
Ms Green said that after going public with her allegations she was contacted by two other women who also said they had been assaulted by the rapper.
One reported the alleged assault in Southend, while another said she was attacked after a gig in Koko, in Camden, north London, in June 2016.
Details of both allegations have been included in the lawsuit, which identifies the women only as 'Jane Doe 1 and 2'.
Nelly' has launched a counter lawsuit to Ms Green and his lawyer said he firmly denied all of the allegations.
"The recent addition of 'Jane Doe 1 and 2' is completely fabricated and an attempt to give credibility to his accuser's far fetched story.
"Nelly welcomes the opportunity to litigate this case in court. He is not looking for any monetary gain...He expects an apology and recognition that he did no wrong."