The British Transport Police are continuing their investigation after train lines were blocked on a Halifax-bound train.
BTP Officers were called at 4.50pm on April 4 following reports of aggressive behaviour on a train approaching Halifax.
Four people who were believed to be involved were spoke to by officers and their details were taken while enquiries continue.
Northern Rail confirmed on Twitter that police were needed on a train between Halifax and Bradford Interchange.
This caused many trains to be delayed or cancelled by blocked lines.
Many commuters use this line to travel to and from Leeds stations Bramley and New Pudsey - as well as further afield towards Bradford, Calderdale and Manchester Victoria.
British Transport Police have asked anyone who witnessed what happened to contact them by texting 61016 or calling 0800 40 50 40 quoting reference 409 of 04/04/19.
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