The investigation into reports of a rape outside a church in Epsom that led to widespread public disorder will close as police are “confident there was no offence”.

Surrey police received a report on Saturday 11 April that a woman had been raped near a church in the early hours of the morning after leaving Labyrinth nightclub in Epsom.

There was public anger the force had not released the ethnicity of any suspects, leading to protests in the town.

In an update on Thursday, the force said after a “thorough investigation” it became clear the woman in her 20s suffered an accidental head injury after a night out, leading her to make a confused report.

“At the early stages of this investigation, we issued an appeal for any witnesses or information that could help us progress our inquiries and identify any potential suspects,” they said in a statement.

“There was a lack of information in our initial appeal particularly regarding potential persons of interest. This was because the descriptions given were vague and limited.

“We recognise this caused concern among the community. We are now confident that there was no offence, and there were no suspects.”

The force added its detectives carried out an “extensive examination” of CCTV footage of the woman’s movements, as well as house-to-house inquiries, interviews with witnesses and forensic tests.

“To be clear, we take every report of sexual offending seriously, and any such report is treated with sensitivity,” the force said in its statement.

“To do this, it is imperative that the appropriate time is allowed to complete a thorough investigation and support is given to the complainant to progress inquiries at their own pace.

“This limits what information we are able to release publicly,” the force said.

Eggs and beer cans were thrown at police during clashes between officers and protesters on Monday.

Those actions were condemned as “shameful” by Surrey police and crime commissioner Lisa Townsend.

“The mindless scenes we witnessed last night where our police officers were targeted with missiles were nothing short of shameful,” she said on Tuesday.

She added some of those involved in the unrest had travelled from elsewhere to cause trouble, and warned them to stay away.

“I am a firm believer in people’s right to lawful protest, but sadly, some of those present in Epsom yesterday stepped way beyond that line and the type of behaviour we witnessed will not be tolerated,” she said.

“The reality is that a number of those in Epsom last night were not local and have come into the town from elsewhere, clearly with their own agenda.

“My message to those intent on stirring up trouble under the guise of legitimate protest is: stay away from Epsom.

“If you involve yourself in disorder, the police will take robust action and I expect you to face the full force of the law.”

Four people were arrested after the items were thrown at police in riot gear on Monday evening, and one man appeared to try to climb on top of a police van.

It was the second protest in the town after the rape allegation.

On 15 April, footage posted on social media showed a large crowd of protesters had congregated in the town centre.

Dozens of police officers could be seen wearing helmets and holding shields, with objects appearing to have been thrown at them.

The protest was promoted online by Danny Tommo, a former associate of rightwing activist Tommy Robinson.