German police are stepping up their investigation into the brawl between British heavyweights David Haye and Dereck Chisora in February.
The Londoners clashed at a post-fight press conference following Chisora's February 18 defeat by WBC champion Vitali Klitschko.
Chisora was arrested, questioned and released by detectives at the time, while Haye left the country before officers had chance to speak to him.
The investigation went quiet for two months but Munich police are currently questioning people present at the press conference and collecting witness accounts.
Some of those in attendance have received e-mails from detectives asking for their version of events and asked questions such as who instigated the brawl and what was said by each party.
After Chisora's spirited loss to Klitschko, Haye - who had been working as a television pundit - appeared at the post-fight press conference and got involved in a verbal spat with Klitschko's manager Bernd Boente.
Chisora and Haye then traded trash talk before Chisora left the stage, removed his robe and went face-to-face with Haye.
Haye was then seen punching Chisora's face using a fist which happened to be holding a glass bottle and the two grappled on the floor.
Haye then fought with Chisora's trainer, Don Charles, and swung a camera tripod at his head, only for it to hit his own manager, Adam Booth.
Chisora, who claimed to have been 'glassed', was also seen holding a bottle at one stage and also shouted threats about shooting Haye, before the chaos calmed.
Chisora was arrested the next day while officers went to Haye's hotel in the early hours only to find he had already departed.
Chisora has since been handed an indefinite ban by the British Boxing Board of Control while Haye - who is officially retired - is not accountable until he applies for a new license.