Paramedics and police have been called to Leeds Bus Station after a man was taken seriously ill.
Emergency services were alerted by bus station staff just after 12.30pm today.
A West Yorkshire Police spokesman said the man in his 70s had been taken to Leeds General Infirmary in a serious condition.
Police remain at the scene, although the circumstances are not believed to be suspicious.
First Bus had warned that there might be some disruption to services due to the incident.