Emergency services were called to the £60m Manchester Science Park on Tuesday afternoon after it was reported a man had fallen from a significant height.
A Willmott Dixon spokesman said: “We can confirm that an incident took place on our site on Greenheys Lane at Manchester Science Park this afternoon, 4 March, involving a member of the public who gained unauthorised access.
“The site is now closed, and the project team are cooperating fully with the emergency services as they investigate the incident.
“Our thoughts are with the person’s family at this difficult time, and we will also offer full support to our people and supply chain members on site given the tragic situation that has occurred this afternoon.”