West Ham threatens lifetime bans for bus-attack culprits

Those responsible for the damage to Manchester United's coach Tuesday will be banned for life by West Ham United, the club's co-chairman David Sullivan has vowed.

Sullivan reached out to United and apologised for the attack, which saw several supporters throw bottles and cans at the team bus as it arrived for the final match at Upton Park.

Related: West Ham fans wreak havoc before Boleyn Ground send-off

Before discovering the details of why the bus was delayed 50 minutes when it was less than a kilometre away from the Boleyn Ground, Sullivan initially believed United was to blame and described West Ham fans as "over-exuberant."

His tone, however, changed Wednesday in a statement detailing how the 112-year-old stadium's send-off was somewhat spoiled by a "very small minority" of supporters ahead of West Ham's 3-2 win.

Related: West Ham fights off Manchester United in thrilling Boleyn farewell

"Sadly, the actions of a very small minority of people outside the ground prior to kick-off risks overshadowing those celebrations. I want to be clear - their behaviour was completely unacceptable and does not represent our club or our values.

"When I was asked about the incident prior to yesterday's game, I was unaware of the damage that had occurred to the Manchester United team bus. I want to apologise to Manchester United for that damage and assure them that we will be doing all we can to track down those responsible and ban them for life.

The Football Association also announced it will open an investigation into the actions ahead of the encounter, in addition to items being thrown inside the stadium.