Now Playing: Video shows Pulse nightclub gunman on night of massacre

Now Playing: Gunman has taken hostages at largest veterans care facility in US: Police

Now Playing: Surveillance video released from moments after Parkland gunman opened fire

Now Playing: New information on alleged gunman in Florida school massacre

Now Playing: Facebook bans entities allegedly responsible for collecting and sharing user info

Now Playing: Kevin Esterly in police custody after allegedly fleeing to Mexico with 16-year-old gi

Now Playing: Cirque du Soleil performance takes deadly turn

Now Playing: More than 100,000 people still without power after Hurricane Maria

Now Playing: Major storm headed East

Now Playing: Woman learns hard lesson about vetting Airbnb renters

Now Playing: Gunman shoots and kills his ex-wife at Thousand Oaks Mall in California

Now Playing: Guardian angel helps Loyola Chicago basketball team enter the Sweet 16

Now Playing: Nurse takes stand in murder trial of Atlanta businessman

Now Playing: Facebook suspends British-based data company used by Trump campaign

Now Playing: Emergency crews recover remaining victims of deadly bridge collapse

Now Playing: Missing teen from Pennsylvania found safe in Mexico

Now Playing: 16-year-old Amy Yu found in Mexico

Now Playing: Teammates cheer on fellow high school football player who beat cancer

Now Playing: FBI warns parents about 'virtual kidnapping'

Now Playing: Teens on dangerous high speed chase through local streets