One boy remains in hospital receiving treatment while the other boy was discharged from hospital on Wednesday 4 October.
Gwent Police received a report of a medical emergency in Hengoed Road, Hengoed, at around 2.15pm on Sunday 1 October.
Two boys were taken to hospital for injuries believed to be linked to an explosion of a firework.
A nine-year-old boy from the Cefn Hengoed remains in hospital in Bristol, where he continues to receive treatment and is in a stable condition.
An eight-year-old boy from the Hengoed area was discharged from hospital on Wednesday 4 October after sustaining facial injuries.
Superintendent Mike Richards said:
“Our officers have already spoken to several people as part of our enquiries and this work is continuing.
“We’re hopeful that within the next few days we will have spoken to both boys, ensuring that they are both ready to speak to our officers and with the full support and co-operation of their families.
“There has been a substantial amount of information passed onto us by the community and we’re grateful to everyone who has got in touch with us so far with information to assist.
“We’ve looked into these details and have found that some of the information provided to us has proved to be inaccurate.
“There is a lot of speculation about what has happened, so we’re asking people to refrain from commenting about these matters on social media as some of these comments are proving unhelpful and placing innocent members of our communities, including children and young people, at risk of harm.
“Our aim is to understand what has happened in Hengoed which has sadly resulted in two boys receiving significant injuries as well as a great deal of emotional pain for their families and friends.”
Anyone with information is asked to call 101 or send us a direct message on social media, quoting log reference 2300332856.
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