Passengers at London Euston have faced queueing, severe delays and cancellations to their trains while returning home from the Jubilee celebrations.

Train operator Avanti West Coast said all lines were blocked shortly after 5.30pm on Sunday due to an “emergency incident” between Watford Junction and Milton Keynes Central.

It later confirmed in a statement that the incident involved a person being hit by a train between the two stations, adding that trains may either be delayed, cancelled or revised following the incident.

Images and footage taken at London Euston station showed people queueing outside as they waited to board their trains.

The delays came after thousands of people flocked to London to celebrate the Queen’s Platinum Jubilee celebrations, which drew to a close on Sunday evening.

One passenger, who was waiting with a friend at the station, told the PA news agency: “A lot of trains were cancelled and the gates were shut so no one could come in for a while.

“My friend was trying to get a train to Liverpool – and that happened eventually about 25 mins ago (it was supposed to leave at 8.05).

“I was fine because I wasn’t taking any trains, I was just accompanying my friend. And the mood overall was ok – I didn’t hear any shouting or nervous people.”

A statement on Avanti West Coast’s website posted shortly before 8.30pm said: “Following a person hit by a train between Watford Junction and Milton Keynes Central all lines have now reopened. Train services running through these stations may be cancelled, delayed by up to 120 minutes or revised. Disruption is expected until the end of the day.”

It added that passengers with Avanti West Coast tickets can use their tickets on West Midlands Railway, London North Eastern Railway, East Midlands Railway and CrossCountry services until further notice.

At least seven trains from London Euston to Liverpool, Manchester, Birmingham, Preston, Wolverhampton and Milton Keynes were listed as delayed on National Rail’s website.