The Celtic manager Neil Lennon was attacked by a fan during his team's 3-nil Scottish Premier League football victory over Hearts in Edinburgh.
Just after Celtic scored their second goal four minutes into the second half, a fan ran from a stand for home supporters and tried to attack Lennon by the dugout.
The fan was eventually wrestled away by stewards and police but the incident sparked more crowd trouble as Celtic fans clashed with stewards.
The incident was the latest in a succession of problems for former Northern Ireland and Celtic captin Lennon, who has received death threats on several occasions and retired from international football because of them.
A package containing bullets was intercepted last month at a sorting office in Northern Ireland, one of a series of suspicious packages that have been addressed to him.
Celtic's victory kept the Scottish Premier League title race alive going into this weekend's final round of fixtures when they host Motherwell.
Their arch-rivals Rangers, who visit Kilmarnock, are one point ahead but with an inferior goal difference.