@pbsnews: Federal safety officials are investigating the cause of a news helicopter crash in Los Angeles that killed three people. The helicopter was reporting on a bus collision for NBC4 Los Angeles on Tuesday when it went down around 7 p.m. Fire officials say both pilot George Marciniw and reporter Eliana Moreno were killed. A bystander on the ground, Edy Gutierrez Mejia, 29, also died in the copter crash. A motorist has been arrested for causing the crash the news crew was covering. Authorities say she slammed her SUV into a city bus, killing at least two people. #pbsnews #news #losangeles #crash #investigation #helicopter