The Prime Minister has joined furious Calderdale politicians in condemning the Northern Rail crisis.
Her official spokesperson said on her behalf: "It is important we get to grips with this issue quickly; the current passenger disruption is letting people down and is unacceptable.
"She said the inquiry announced on Monday must find out what went wrong and ensure the misery currently being endured by the public never happens again.
"Fixing this is an absolute priority and as the Transport Secretary set out in the House yesterday, people must be properly compensated.
"The Prime Minister added that the new timetable will deliver hundreds more services up and down the country when properly implemented but in the meantime we need to urgently minimise the disruption."
It comes after Halifax MP Holly Lynch said that the problems have existed for some time.
She said: “I’ve been appalled by the terrible service being provided by Northern on our local trains and across the North.
“Although the new timetable has undoubtedly made things worse, these issues have been going on for much longer. I had already written two letters to the Transport Secretary earlier this year urging him to take action on the Calder Valley Line as delays and overcrowding were so bad and raised the ongoing issues directly with Theresa May at PMQs.
“It’s been great to see newspapers across the North unite in their demands for better services. I hope that now the Government will do all in its power to help get things working again. The ‘Northern Powerhouse’ rhetoric already seems like a bad joke and Ministers will not be forgiven if they fail to resolve the current rail crisis”.
Calderdale Council Leader Tim Swift wrote an open letter to Northern Rail boss David Brown, saying that businesses were suffering as a result of the chaos.
He said: “We have major employers in the borough, including Nestles International, Covea Insurance and SSP which have their global headquarters in Halifax. The Lloyds Banking Group is also located here. Our businesses and our residents rely on these vital connections with the major towns and cities across the North, including Leeds, Bradford and Manchester.
“It’s extremely disappointing, particularly given how relentlessly we have been working to bring key improvements to the rail network through Calderdale.”