A 72-year-old woman and a dog were killed, and three other people were injured, one critically, in a collision on the northbound 405 Freeway in Westwood Friday.

A 66-year-old man was critically injured while a 60-year-old woman was in fair condition. A second dog was missing, according to the Los Angeles Fire Department.

LAFD personnel responded to the freeway, near the Wilshire Boulevard exit, around 7:15 p.m., the department’s Lyndsey Lantz said.

It was unclear what led up to the collision, and California Highway Patrol personnel were continuing their investigation Friday evening.