Intruders breached the fences and gates that surround Florida’s four busiest airports at least 37 times since the beginning of 2004. An Associated Press investigation found 14 incidents at Miami’s airport, 13 at Tampa, seven at Orlando International and three at Fort Lauderdale-Hollywood International.

The breaches were among at least 268 at the nation’s busiest airports between January 2004 and January 2015. None involved a terrorist plot.

In 19 cases, security nabbed a person who scrambled over or under a fence. Last year at Orlando, a man climbed into a jet’s wheel well and stayed for hours. In 2010 at Fort Lauderdale, a man boarded an empty jet after stabbing a plumber. Airports say breaches are relatively rare. Security measures include fences, cameras and patrols, but there are gaps.