Further trains would be delayed, cancelled or diverted via Seven Sisters, a spokesperson added.
London Fire Brigade (LBF) said 14 engines were used to tackle a grass fire, near Lea Road in Waltham Abbey, which is close by. It added, the fire was now under control.
On its website LFB said at the height of the fire, about 14 hectares of grassland was alight. Crews used water backpacks and wildfire beaters to tackle it.
It is unclear whether this is a separate blaze and the BBC has asked the service how many incidents it is dealing with in the area.
Greater Anglia also said Network Rail officers were on site, “working as quickly as possible” to help restore train services to normal.
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