Honolulu vehicular homicide investigators are looking for one vehicle — and possibly others — that hit and killed a 21-year-old Navy sailor walking on the H-1 freeway and then fled the scene early this morning.

A 2007 Nissan Altima driven by a 22-year-old, Mililani man also hit the sailor but did stop and called police around 2:17 a.m., police said.

Investigators are still trying to determine why the sailor was walking in the west-bound lanes of the H-1 just before the Makakilo off-ramp. They don’t know whether drugs or alcohol were involved.

The sailor was hit by one vehicle that fled the scene and possibly by another vehicle that also fled, police said. He was pronounced dead at the scene.

The crash was the 10th traffic fatality on Oahu this year, compared to 13 for the same time last year.

The collision temporarily forced the closure of the H-1 freeway near Makakilo.