The airport would only confirm that an 'incident' happened this morning and said three people have been taken to hospital.
It said the runway would be closed until further notice.
A statement, posted on Twitter, said: "We can confirm an incident occurred today involving a light aircraft at 09:39. A pilot and two passengers were onboard and have been taken to hospital. Our runway will remain closed until further notice while a thorough investigation is carried out.
"We would like to thank the emergency services, on-site staff for their quick response."
The runway closure has led to some flights being diverted to Newcastle Airport.