A young Chelsea supporter was treated by paramedics after a flare was thrown into the away end at Anfield on Sunday.
Police confirmed they are investigating after the fan, who they believe to be nine years old, was taken to the first aid centre at the stadium as a result of having a panic attack when the flare landed in the lower section of the Anfield Road stand.
The incident took place shortly after Sadio Mane opened the scoring for the Reds .
A Merseyside Police statement read: "Merseyside Police can confirm that we are investigating after a flare was reported to have been thrown during the Liverpool FC vs Chelsea FC match yesterday afternoon (14th April)."
"The incident was reported to us at 5.40pm, shortly after LFC scored their first goal, that a flare was thrown from the upper section of the Anfield Stand.
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"Following this, at around 6.20pm, officers received reports that a young Chelsea fan, believed to be nine years old, had been taken to the first aid centre where he was treated by St Johns Ambulance staff after suffering a panic attack as a result of the flare.
"At this stage, it is not clear who threw the flare, however investigations are ongoing and police are urging anyone with information to come forward quoting log 322 of 14th April."
Pictures posted by Twitter user DJSLD, who has since made their account private, appeared to show the moment immediately after the flare was thrown into the Chelsea section.
Liverpool won the game 2-0 and returned to the top of the Premier League with the victory.
