The A45 between Weedon and the M1 for Northampton has been closed this morning (Tuesday).
A 'police incident' has forced the closure of the road in both directions stretching along the bypass from Weedon to the M1 junction 16.
Highways England, who are supporting police at the scene, tweeted: "#A45 between #WeedonBec and #M1 now closed both directions due to a @NorthantsPolice incident. Please plan your journey around this."
The road was originally closed westbound following the incident at 6.30am. A full closure is now in place.
There is congestion on surrounding routes including the A5 and through the villages of Flore and Upper Heyford.