The death toll from a crash along the Hume Highway near Yass on Sunday morning has risen to two, after a second man died in hospital on Sunday night.

Emergency services were called to the scene near Rock Lodge Road, Lade Vale at around 2am after reports a Mazda 6 and a Pantec truck collided head-on.

The 23-year-old driver was flown to Canberra Hospital in a critical condition following the crash where he died on Sunday night.

It follows the death of his 21-year-old passenger who is believed to have gotten out of the vehicle following the crash and was struck by a second truck.

The two truck drivers, aged 32 and 65, were uninjured and taken to Yass Hospital for mandatory testing.

A crime scene has been established, which will be examined by specialist police from the Crash Investigation Unit.

A report will be prepared for the coroner.

Listen to the latest news below: