Quick-thinking L.A. County Deputies activated the escalator's emergency stop switch to prevent further harm to the child, according to a LAFD press release.
Crews responded to the courthouse on at 14400 Erwin Street Mall in the Van Nuys Civic Center shortly before 9 a.m.
The 17-month-old boy was descending from the second to first floor, when his left index finger was caught in the comb-and-groove of the foot tread.
He did not become trapped in the escalator, but his detached finger was missing in the mechanism.
Paramedics described the boy as being calm and exceedingly brave throughout the ordeal, according to the statement.
The paramedics stemmed the blood loss with a dressing and bandage and placed the child and his mother into an ambulance as colleagues searched for the missing finger.
Firefighters disassembled the massive machinery in order to find the boy's finger.
Power tools were used to deconstruct the device piece-by-piece.
More than a dozen firefighters worked non-stop for nearly 90 minutes until they found the missing finger. The finger was quickly placed in a cool, sterile dressing inside a clean plastic bag.
The finger was transported to the Richie Pediatric Trauma Center at Northridge Hospital, where surgical teams awaited a chance to restore the child's missing digit.
