Trains were delayed and cancelled from St Albans this morning after police conducted a search of the carriages at rush hour.
Officers boarded and held a train after British Transport Police received a call at about 6.55am from a member of the public.
It is unclear what the tip was about or if the search was successful.
As some lines were blocked two trains cancelled and one was delayed by 40 minutes.
Were you on the train when police boarded? Let us know what happened at hertsad@archant.co.uk
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