Two people have died in separate Northland crashes overnight.

A person died in a single-vehicle crash on Arapohue Rd near Rowland Rd, southeast of Dargaville.

Emergency services were notified shortly before 7.50pm.

They attended a second serious crash on SH1 at Oakleigh, south of Whangārei about 1.30am.

One person died at the scene and a second was taken to hospital in a serious condition.

Fire and Emergency northern shift manager Paul Radden said two crews from Whangārei attended.

The Serious Crash Unit is investigating both crashes.