The police helicopter is searching an area in Northampton near where officers have closed a road.
A police spokesman said a closure has been in place in London Road, Far Cotton near Penrhyn Road from about 6.25am.
He said it is to allow emergency services to deal with an incident.
He added: "Please avoid the area for now. Updates to follow."
A police helicopter was hovering over Far Cotton and Delapre for over an hour until about 6.30am.