Video from one Twitter user shows water from several points gushing into Tufnell Park Road. Police confirmed they had closed the street between Campdale Road and Huddleston Road.
The burst was first reported to the emergency services at 6.10am.
“Route 4 is subject to diversion following Tufnell Park closure due to road surface collapsing,” Transport for London tweeted from its bus alerts account (@TfLBusAlerts.
TUFNELL PARK ROAD N7: Route 4 subject to delay and diversion Tufnell Park Road N4 closed in both directions due to road surface collapse