SAN JOSE -- A woman was killed Saturday when her car crashed into a tree in a West San Jose neighborhood, police confirmed Monday.

The cause for the crash remained a mystery as traffic investigators work on the case, San Jose police Officer Albert Morales said.

Police were called about 5:45 p.m. Saturday to the 2700 block of Leigh Avenue for reports of a small car that struck a tree, Morales said. The driver, a 33-year-old woman whose identity has not been released, was pronounced dead at the scene.

No one else was injured and no other vehicles were involved. Morales said there was immediate evidence of either intoxication or that a medical emergency preceded the crash. Further details were not released pending the completion of the investigation.

Anyone with information about the collision can contact SJPD's traffic unit at 408-277-4654.

Contact Robert Salonga at 408-920-5002. Follow him at Twitter.com/robertsalonga.