Cristiano Ronaldo was approached by fans on separate occasions during and after the clash at Old Trafford.

Shortly after kick-off, a fan ran across the pitch with his hand down the back of his trousers before being restrained by stewards.

Two fans also tried to get to Ronaldo after full-time on his return to his former club.

UEFA have opened disciplinary proceedings against United, with a hearing set to be held on November 22.

Greater Manchester Police have stated that one man in his forties was kept in custody overnight, having been arrested on suspicion of pitch invasion.

It is the second time United have been charged this season by UEFA - although they have escaped punishment for their late arrival at Old Trafford.

United were last week fined €15,000 euros (around £13,000) by UEFA for their late arrival and the subsequent delayed kick-off of their Champions League match against Valencia.