A family is mourning the loss of a second son after a South Otago volunteer firefighter was killed in a crash.

Logan Sinclair, 34, died after a crash on Clutha Valley Rd, in Greenfield, Otago, after emergency services were called to a single vehicle crash around 1.55am.

The father of one was the sole occupant of the vehicle, which went off the road between Craig Rd and Allangrange Rd, according to police.

Inquiries into the circumstances of the crash were under way.

Clutha Valley Volunteer Fire Brigade chief fire officer Richard Hunter told Stuff his crew were still in shock after attending a fatal accident on Saturday morning involving “one of our own, so soon after the death of another fire fighter 14 months ago”.