Authorities are warning sailors to avoid a large zone in the Atlantic Ocean near the Spanish coast due to orcas who have been ramming boats.
Two people had to be rescued over the weekend after an encounter with a group of orcas caused the boat to sink in the Strait of Gibraltar.
Crew members said the orcas, also known as killer whales, had slammed the hull, damaged the rudder and caused a leak. A nearby tanker rescued the pair, according to the BBC.
It is an ongoing problem in the area. There have been five sinkings in the waters in the past few years that are believed to be attributed to the same pod of orcas, according to the New York Times.
Scientists from Spain, Portugal and Morocco have been studying the interactions in the so-called "orca alley."
Wildlife officials say the orcas are not trying to attack the boats but appear to be trying to play.
Officials say that boats should not stop if the orcas start approaching them but they should sail toward shallower waters toward the coast.
They are also alerting sailors to avoid the area of the Gulf of Cádiz and the Strait of Gibraltar during the months of April to August, and sail as close as possible to the coast within the security limits.
People on small boats are ured to make sure they are in areas of the boat that provide the greatest possible protection against possible sudden movements that could cause injuries or falling into the sea, and against blows caused by the orcas.
The good news is that the number of interactions appears to be declining.
The Atlantic Orca Working Group said the number of orca interactions with boats this year had dropped about 40 percent from previous years.