Woman killed in wreck overnight on SR 509

A woman was killed early Saturday after her car left state Route 509 on the Tacoma Tideflats and hit a tree, according to police.

The crash happened about 3:30 a.m. on northbound Route 509 at Alexander Avenue, police spokeswoman Loretta Cool said.

The woman was driving north when her car hit the tree, Cool said. She was pronounced dead at the scene of the crash.

The woman’s identity and the cause of the crash are unknown, Cool said. The highway was closed for six hours as police investigated.