A university professor and former radio announcer succumbed to gunshot wounds early on Saturday, after being shot by unidentified assailants along the national highway in Magsingal municipality, Ilocos Sur the previous night.

According to initial reports from investigators, Mario Contaoi, 52, was riding his motorcycle northbound along the national highway in Barangay San Ramon when he was attacked by men riding a motorcycle, at around 10:30 p.m. Friday night.

Contaoi was rushed to the Ilocos Sur District Hospital-Magsingal and later transferred to a private hospital for treatment, where he succumbed to multiple gunshot wounds early on Saturday.

Authorities recovered six empty cartridges from a .45-caliber pistol at the crime scene.

Investigators have yet to determine the motive for the killing.

Contaoi was a volunteer radio reporter for Vigan City radio station DZNS. He was also a professor at the University of Northern Philippines (UNP). He hosted the radio program of UNP on DZNS when he was still the Director of the External Affairs of the university. - with reports from Ria Galiste and Bryan Realogo, ABS-CBN News