It was Mr Dhaliwal's first night working as a security guard, and he was on a trial shift for CNE, a security company sub-contracted by Fulton Hogan. He was the only person guarding the site and was found by two construction workers who went to pick up a vehicle.
Police said last week there were obvious signs of injury to Mr Dhaliwal's body, but were unable to say whether those had been inflicted by another person or were the result of a workplace accident.
It is understood there was blood around Mr Dhaliwal's head and face, and on the ground where he was found.
Police are understood to be looking for two men seen "misbehaving" in the Selwood Rd area near the Fulton Hogan site early on Friday.
Although they do not believe the men contributed to Mr Dhaliwal's death or injuries, they want to identify them and ask if they saw anything or anyone else suspicious in the area.
Yesterday the police cordon around the site had been removed but detectives were scouring the area for clues. They could be seen checking the ground near the concrete slab and walking up and down the fenceline.
Detective Sergeant Eugene Pickett said the scene had been released to Fulton Hogan, which decided to keep it closed until today. This was out of respect for Mr Dhaliwal, whose car was still parked at the site, and to give staff time to deal with the shock.
Mr Pickett said police were "keeping an open mind" about what happened on Friday morning, but he did not believe it was a case of murder.
Detective Senior Sergeant Stan Brown would not say how Mr Dhaliwal died, stating his family in India had not been given the specific details yet. Until then, police were withholding that information.
"Whatever happened was sudden," he told the Herald.
When asked if Mr Dhaliwal's death was suspicious Mr Brown said: "We still don't know. We'd like to know one way or the other though.
"There is no indication whether this is an accident or whether someone's done some damage. We still don't know what investigation we're looking at."
Mr Brown said the post mortem examination had clarified several things about Mr Dhaliwal's death.
"But the results still don't put it one way or the other."
Mr Brown said police had reviewed images from security camera in the area, but they did not cover the area where Mr Dhaliwal was found.
Officers have also spoken to two people, including one of Mr Dhaliwal's flatmates, about calls he made to them from his cellphone while at work on the night he died.
"The calls were not concerning and everything seemed quite normal," Mr Brown said.
Police were still working with Mr Dhaliwal's flatmates and friends to piece together what may have happened, he said, but none of them was a "suspect" or person of interest.
Mr Dhaliwal was born in India and came to New Zealand about two years ago to study.
