Col Rabih Alenezi says he was ordered to evict villagers from a tribe in the Gulf state to make way for The Line, part of the Neom eco-project.
One of them was subsequently shot and killed for protesting against eviction.
The Saudi government and Neom management refused to comment.
Neom, Saudi Arabia’s $500bn (£399bn) eco-region, is part of its Saudi Vision 2030 strategy which aims to diversify the kingdom’s economy away from oil.
Its flagship project, The Line, has been pitched as a car-free city, just 200m (656ft) wide and 170km (106 miles) long - though only 2.4km of the project is reportedly expected to be completed by 2030.
Liberals will never protest the murder of brown people