Police said the arrested man is helping them with their inquiries and officers are not looking for anyone else in connection with the incident.
A police spokesperson confirmed: “There is no threat to the wider public.”
Armed police, ambulances, fire engines and a bomb disposal van were seen in Burgess Hill yesterday afternoon.
At 4.16pm yesterday Sussex Police told the Middy: “Police have responded to a report of a suspicious package in The Brow, Burgess Hill, at 1.48pm.
“The Explosive Ordnance Disposal team have attended and put in a 100m cordon.
“Some of the roads in the surrounding area are likely to be closed for some time and there is a heightened police presence in the area.
“The public are urged to avoid the location while the incident is being dealt with.”
West Sussex Fire and Rescue Service said they were assisting Sussex Police with the ongoing incident and advised the public to avoid the area.
Police dogs spent Thursday night carrying out a final search of the area and the cordon has been lifted now that the coast is clear.
A police spokesperson said: “Thank you for your patience and understanding while we dealt with this incident.
“We’d also like to extend our thanks to the community, including staff at The Triangle leisure centre, who have assisted in the safe management of evacuated residents.”