What are the consequences for a person who violates a launch exclusion zone?

The SpaceX launch attempt on Sunday 02/28/16 had problems partly because of a delay due to a boat in the launch exclusion zone. Elon Musk tweeted

"Launch aborted on low-thrust alarm. Rising oxygen temps due to hold for boat and helium bubble triggered alarm,"

The cost to SpaceX for that is significant, as is the delay for the customer with the payload. Is there a cost to the owner of the boat? Is there a fine or other consequence? Does this vary according to the nation or state where the launch complex is sited?

• Good answer on the US specific case. As the title is more general, does anyone know what practices apply in other countries? – Puffin Mar 2 '16 at 20:18
• @Puffin I wondered about that too, but it was hard enough to track down the US information and i left it. – kim holder Mar 2 '16 at 20:30
• getting cooked to a degree commensurate with the distance to closest approach to the exhaust? – uhoh Feb 13 at 2:23

This article from Florida Today has a comprehensive look at the particular violation on Sunday. In this case, the violator was a tugboat hauling a barge.

The Coast Guard said the tug boat and barge were about 30 miles form shore and within the safety zone... violators of the safety zone can be fined if they are within 12 miles U.S. territorial waters. The Coast Guard does not have the authority to fine boats outside territorial waters. A boat could, however, still face fines for equipment violations... A commercial vessel such as the tugboat is required to have an automatic identification system and radio. If the vessel strayed into the area because it did not have the required equipment it could be fined $1,000, even if it was outside territorial waters. "A lot of people are asking if they could be fined," he said. "They could be fined for not using AIS system." West said the Coast Guard had not yet determined what, if any, action would be taken against the tugboat owners. A notice regarding a launch from Wallops Flight Center listed the penalty for violation of the launch exclusion zone: Every person and every corporation which shall violate such regulations shall be deemed guilty of a misdemeanor and, on conviction thereof in any district court of the United States within whose territorial jurisdiction such offense may have been committed, shall be punished by a fine not exceeding$500, or by imprisonment not exceeding six months, in the discretion of the court.

Because it mentions 'any district court in the United States', this would seem to be a federal regulation in the U.S..

A case of a leisure boat that caused the scrub of the Antares launch of Cygnus last October (which later exploded at liftoff) was described in this Air and Space article this way:

“Boats out that far in the ocean are supposed to be monitoring marine band channel 16,” Beutel says. The effort to warn away at-risk boasts is robust: Nine hours prior to launch time, Wallops begins broadcasting a warning on channel 16. Four hours before, a complement of “seven or eight” boats from the U.S. Coast Guard, Coast Guard Auxiliary, and Virginia Marine Police begins patrolling and clearing the launch area. An hour after that, they’re joined by three aircraft—a radar airplane, a spotter airplane, and a helicopter—all on the lookout for stray boats.

The leisure boat that scuttled last night’s planned launch was spotted early in the launch count, but it did not respond to numerous attempts at radio contact. The spotter plane’s subsequent attempt to signal to the boat by circling it and dipping one wing, as is standard practice when radio contact fails, also went unanswered. The boat was traveling at only about four knots. “There was no way it was going to be able to clear the hazard zone in time for the launch,” Beutel says.

There was no mention of anyone being fined. Elsewhere it was implied that violators are given some leeway and fines may be deferred depending on circumstances. From SpaceFlightNow:

Boats violating restricted rocket safety zones periodically cause launch delays, but missions with long launch windows give vessels more time to vacate restricted areas... An Atlas rocket launch from Cape Canaveral — a spaceport run by the U.S. Air Force — was scrubbed in 2000 after boats strayed into restricted waters during a fishing tournament scheduled the same day.