A demand for places for this year's Junior and Mini Great North Run has led to organisers to put a halt to its entry website.
The Great Run has said that due to a technical error, based on levels of demand, it is not taking entries for 2019 Simplyhealth Junior and Mini Great North Run.
Earlier today it has announced places could be booked, with efforts under way to get the online system up and running again.
A spokeswoman said: "Entries for the 2019 Simplyhealth Junior and Mini Great North Run are expected to re-open tomorrow, Tuesday, February 12.
"We’ll update again later on today with timings, across our social channels, and via email.
"If you’ve signed up to the Reminder Service, there’s no need to re-register.
"Thanks again for your continued patience."
Organisers of the SimplyHealth Junior and Mini Great North run say 9,000 children are set to take part in the event on the NewcastleGateshead Quayside, which takes place on Saturday 7 September.
Both the Junior and Mini events are expected to reach full capacity extremely quickly, with the children’s run taking place a day before the world-famous Simplyhealth Great North Run.
It has been a popular fixture in the region for over 30 years and has grown to be the biggest children’s running event in the UK.
The event is a must-do for budding runners, with entries in almost as much demand as the half marathon itself, with entries being limited to four per person.
The thousands of athletes and fun runners will set off in waves across the day, heading across the Swing Bridge to the Gateshead side, along a 1.5km and 4km courses, for ages three to 16.
The final stretch of both courses then takes children over the Gateshead Millennium Bridge before they cross the finish line on the Newcastle side of the Quayside.
The Simplyhealth Great North 5k will also return to the Quayside, with over 1,000 runners taking on a shorter running route across a fast and flat course.
The events are part of one of the biggest weekends of sport in the North East’s calendar, culminating in the world’s biggest half marathon with 57,000 participants.
Street-level athletics will also head to Stockton High Street and riverside when the Great North CityGames moves to Stockton-on-Tees in 2019.
The world-class sporting event, which has been staged on the NewcastleGateshead Quayside for ten years as part of the iconic weekend, will be held in a new location for the first time.
For more information and to enter the Simplyhealth Junior and Mini Great North Run or the Simplyhealth Great North 5k, visit: Greatrun.org/North.