VIDEO: 8 killed, 5 injured in mass shooting in Indianapolis

(CNN) -- A gunman opened fire outside and inside a FedEx Ground facility near Indianapolis' main airport Thursday night, killing eight people, wounding several others and sending witnesses running before taking his own life, police said.

Police were called to the facility at about 11 p.m. local time for what has become the country's deadliest shooting since 10 people were killed March 22 at a grocery in Colorado.

The coroner's office had yet to officially identify any of those killed as of late Friday morning. Investigators are trying to determine the motive and were searching what they believe is the gunman's home, FBI special agent in charge Paul Keenan told reporters late Friday morning.

"Nothing we learn can heal the wounds of those who escaped with their lives, but who will now ... endure the memories of this horrific crime," Indianapolis Mayor Joe Hogsett said at the same news conference.

The video above includes a press conference Friday morning, video of the scene Thursday night (no audio) and a sound byte from a witness who heard gunshots last night.