It is understood that a number of arrests have been made outside the ground ahead of the match between Hearts and Celtic – scheduled to kick off at 8pm.
Footage posted on social media shows rival fans kicking and punching one another, while police try to separate them.
Under new Scottish Premiership rules, the opening game of the season at Tynecastle was only meant to be attended by a selection of the home side’s season-ticket holders.
But alongside some 5,200 Hearts spectators, a large number of ticketless Celtic fans have also gathered outside the stadium.
Police Scotland has been contacted for comment.
Updates to follow.