Police officers and an air ambulance were seen on the football pitches at the end of School Road at around 5.15pm today, shortly after a sudden thunderstorm hit the area.
Four police vans, a rapid response vehicle and an air ambulance van remained at the scene at 6.30pm. The field off Jepson Way remains closed.
A police spokesman said: "We were called shortly after 5.05pm today, Tuesday, May 11, to a football field on School Road, Blackpool to reports a child had been injured.
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"He has since been taken to hospital, where he remains with serious injuries.
"Road closures are currently in place and we would ask that people avoid the area and motorists find alternative routes where possible."
It is believed the boy was taking part in a one on one football training session when he was hit.
Spirit of Youth FC secretary Daniel Pack said: "Unfortunately, we don't know much at the moment. We extend our sincerest condolences to the family involved. We are all very upset and saddened by this whole thing. The whole club is shocked."
Traffic was diverted from the area.
Anybody with information about the incident, or who witnessed it and has not yet spoken to police is asked to call 101 quoting log 1169 of May 11.
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