A man has been arrested on suspicion of causing the death of 29-year-old Philip Capper through careless driving.
Mr Capper had been a passenger on a John Deere tractor which left the Back Road at Drumbo on Friday night.
The deceased is originally from the Annaghmore area.
A 22-year-old man was arrested on suspicion of causing death by careless driving.
He has since been released pending further police enquiries.
Police in Lisburn are continuing to appeal for witnesses to Friday night’s collision – or anyone who has any dash-cam footage – to get in touch on the non-emergency number 101.
Mr Capper’s funeral will take place at Banbridge Baptist Church on Wednesday, followed by interment at Kernan Cemetery in Portadown.