A police spokesman said the incident occurred under the Te Irirangi ' />

A person is dead after being hit by a truck on Auckland's Southern Motorway.

A police spokesman said the incident occurred under the Te Irirangi Drive overbridge near Manukau.

The motorway is heavily congested and the northbound lane is closed as police investigate.

The Manukau on-ramp is also closed to ease traffic congestion.

It was not known how the person came to be on the motorway.

- NZPA