Police said Rotoras bore multiple bullet wounds in his body and was rushed to the nearby JR Borja General Hospital by his driver but did not reach the medical facility alive.
A witness told investigators he saw people loitering near the Golden Glow North perimeter fence days before the incident.
The same witness also saw two men walking out of the subdivision after the shooting. A black pick-up truck came to fetch the suspected gunmen, the witness added.
Recovered from the crime scene were empty shells fired from a weapon believed to be a .45 caliber pistol.
Rotoras, who served as the head of the USTP since 2006, was also the president of the Philippine Association of State Universities and Colleges (PASUC) for four consecutive terms.
Elected unopposed for the fourth time, Rotoras was supposed to end his two-year term as PASUC head in 2019.
His colleagues describe Rotoras as a “dedicated public servant” and “workaholic.”
USTP alumnus Alyssa Clenuar, in her post on social media, said Rotoras’ death was “a big loss to everyone” in the university and those that he had extended help in the past.
As of Saturday morning, police said they were still conducting investigation and follow-up operation.
Authorities have yet to establish the identity of the gunmen and the motive for the killing.
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