Two die on WA roads after hitting trees

A 70-year-old man who was missing has been found dead after a motorcycle crash south of Perth.

A West Australian police spokesman said the man was riding from Rockingham to Dwellingup but was reported missing after he didn't return home.

Rockingham police found the man's body at Whittaker, north of Dwellingup, where he had crashed into a tree.

Another fatal crash occurred overnight at Karawara in Perth's southern suburbs.

The spokesman said a 21-year-old Bentley man died after he drove onto a median strip and hit a bollard and a tree around midnight.

The driver was taken to Royal Perth Hospital with serious injuries but later died.