Emergency services including an air ambulance were called after a Merseyrail passenger collapsed.
Several ambulance vehicles and police were called to the scene as commuters were heading into work this morning.
Ambulance officials confirmed the train passenger was taken to hospital in a "serious condition" after suffering what was termed a "medical episode" this morning.
An air ambulance, land ambulance, rapid response vehicle and four senior clinicians were all in attendance after the passenger, a man in his 20s, fell ill on the train at Capenhurst on the Wirral Line.
Merseyrail warned that some trains to and from Chester could be cancelled, delayed or suspended between Hooton and Chester while emergency services went to the man's aid.
A North West Ambulance Service spokeswoman confirmed the man was taken to hospital by land ambulance.
She told the ECHO: "We were called at 7.46am and an air ambulance, land ambulance, rapid response vehicle and four senior clinicians were all in attendance.
"We took a patient, a male in his 20s, in a serious condition to hospital. It is thought he had a medical episode."
Trains were affected until around 9.15am.
