Two men arrested for their involvement in a smoke bomb incident at Villa Park on Sunday have been bailed with "strict conditions".
Assistant referee David Bryan was struck on the back of the neck by the object - thrown from a section of the ground containing away fans - as Andros Townsend celebrated giving Tottenham the lead in a 2-0 victory over Aston Villa.
The duo, aged 25 and 47, remained in custody overnight, but West Midlands Police (WMP) tweeted on Monday morning: "Two men arrested on suspicion of throwing a smoke-bomb at yesterday's Villa v Spurs game have been bailed with strict conditions."
Despite initial reports that the projectile involved was a flare, WMP have since confirmed that it was a smoke bomb, with the Football Association stating on Sunday that they too would launch an investigation.
"We will await the match officials' report and will be speaking to the clubs," an FA spokesman said.
"Such incidents highlight the dangers of pyrotechnics being used in a football stadium."
The incident has been widely condemned, with Tottenham manager Andre Villas-Boas adding: "It should be avoided completely. It touched the linesman and situations like this don't have a place in football. I sincerely hope it doesn't happen again."
WMP have also confirmed that an Aston Villa fan was arrested at the Premier League match for making an offensive salute.