The president of the Hong Kong University of Science and Technology (HKUST) has called for an independent probe into the death of 22-year-old Chow Tsz-Lok, who died earlier on Friday, four days after falling from a carpark in Tseung Kwan O..

HKUST president Wei Shyy also demanded a police explanation for a delay in Chow getting treatment.

"We demand a thorough and independent investigation into the death of our student," Shyy said in a statement, referring to online reports that police blocked access to the student when paramedics sought to reach him.

Shyy said he'd seen footage of the ambulance being blocked by police cars and that ambulance officers needed to walk to the scene, "causing a delay of 20 minutes in the rescue operation of our student".

"We demand clarifications from all parties – especially from the police, regarding the cause of the delay in those most critical moments that might have saved a young life," Shyy said. "We will be outraged if there is no acceptable explanation offered to us."

He said the University had set up a portal which would soon be launched for members of the public to submit evidence related to the case.

"We will pass on the collected information to facilitate the independent investigation," Shyy said, while calling for calm.

The police say new CCTV footage has come to light showing Chow wandering alone in the car park for more than half an hour on Sunday night before he walked up from the second floor to the third, from where they believe he fell.