A sinkhole around two metres wide opened up in Northwood this morning.
Police were alerted to the incident on Pinner Road at 9.50am and were still on scene at midday.
Eyewitnesses report the hole is around one to two metres wide. There are no reported injuries but it is not yet clear whether any vehicles were affected.
The road has been closed in both directions due to emergency repairs being carried out between Addison Way and High Street.
The area around the sinkhole has been cornered off.