Original: In October 1976, an arson caused the destruction of four subway cars and damage to Christie station, resulting in the closure of the Bloor-Danforth Line for three days, and the by-passing of Christie station for some time afterwards for repairs.
Simplified: In October 1976, an arson (a fire set on purpose) destroyed subway cars and damage to Christie station. This caused the closure of the Bloor-Danforth Line for three days, and closed Christie station for some time for repairs.