Two police officers were assaulted in a reported '10-man fight' outside a McDonald's near St Albans in Hertfordshire.
The alleged brawl broke out at around 1.30am on Sunday (December 10) at the eatery on the Bell Roundabout in London Colney.
Officers attempting to intervene were caught up in the action after the reported ordeal both inside and outside the restaurant.
Suspects were interviewed at the scene, but police are looking for further information about the incidents and others who were involved.
Detective Constable Mollie Goodwin said: "Our enquiries are continuing, and I am appealing for anyone with information to please get in touch.
"If you were there during the incident or in the surrounding areas and have information that would help our appeals, please contact me at mollie.goodwin@herts.police.uk."
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You can also report information online at www.herts.police.uk/report, speak to an operator in the Force Communications Room via our online web chat at www.herts.police.uk/contact or call the non-emergency number 101, quoting crime reference number 41/98375/23.
Alternatively, you can stay 100% anonymous by contacting the independent charity Crimestoppers on 0800 555 111 or via their untraceable online form at: www.crimestoppers-uk.org
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