The victim, identified as Siluvairasa Amalanesan, 33, was killed on the spot.
An education official, identified as Christian Rajakone, 47, was rushed to Kilinochchi hospital.
Both were traveling in a motorbike, driven by the deceased, to attend an event at the school.
The ambush was reported around 10:30 a.m. at Sinnavalayan Kaddu in Madhu division in the LTTE controlled area in Mannar district.
Sinnavalayan Kaddu is located in Madhu education zone.
Thamileelam Police rushed to the site and launched a search operation.