Luke 8:34
When they that fed them saw what was done, they fled, and went and told it in the city and in the country.
Cross-reference
Matthew 8:33
Parallel
Matthew 8:33 is the parallel account: the herdsmen flee and report everything to the city.
Mark 5:14
Parallel
Mark 5:14 records the same event — the herdsmen flee and report what happened, confirming the synoptic parallel.