Gunmen boarded a ship in the Gulf of Mexico on Monday night, robbing the passengers and leaving two of them wounded.

It's only the latest attack on oil infrastructure in the Gulf, as fuel theft becomes more common on land and at sea in Mexico.

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A pirate attack on an Italian ship in the Gulf of Mexico that left two sailors wounded isn't the first such incident, and with Mexico struggling to address rising insecurity, it's not likely to be the last.

About eight armed pirates arrived in two small ships and boarded the vessel, an Italian-flagged supply ship named Remas, in the evening on Monday and robbed the crew, according to reports about the incident.

The ship was being operated by the Italian firm Micoperi, which services offshore oil platforms. The incident took place about 12 miles off the coast of Ciudad del Carmen in the state of Campeche in southeast Mexico.

The Mexican navy said Tuesday that two of the roughly 35 people on board were wounded — one shot in the leg and another struck in the head.

The navy said it sent a fast boat to the site of the attack late on Monday. The sailors were taken to a private clinic for treatment, according to local media.

The incident is only the latest attack on oil infrastructure and extraction operations in the Gulf of Mexico.

An oil rig in the Gulf of Mexico. Gerald Herbert/AP

"They're starting to attack ships that are transporting petroleum for Pemex" and providing other services, said Mike Vigil, former chief of international operations for the US Drug Enforcement Administration. "Now I presume this is going to be the wave of the future. They are going to be attacking more and more tankers."

Thieves, sometimes disguised as fishermen, typically arrive in small boats with powerful outboard motors, quickly boarding platforms or other ships to take valuables from crew and other equipment, which is often resold ashore.

Mexico's state oil firm, known as Pemex, has acknowledged the threat, and together with the navy has said it would increase security efforts. Mexican President Andres Manuel Lopez Obrador said in March that the navy would establish a permanent operation at the port of Dos Bocas, Tabasco, his home state, to confront the pirates.

Nevertheless, there have been reports of hundreds of robberies of this kind.

Pemex documents obtained by the newspaper Milenio showed that 197 such robberies took place in 2018, the most out of the past three years and a 310% increase over the 48 attacks in 2016. Those robberies cost the firm at least $11.5 million between 2016 and 2018, according to the documents.

The waters at the southern end of the Gulf of Mexico, off the coast of Campeche and neighboring Tabasco state — where Pemex operates more than 100 platforms — are the most affected.

'Wave of the future'

Forensics workers at the site an oil-pipeline explosion in Tlahuelilpan, Hidalgo state, Mexico, January 19, 2019. AP Photo/Claudio Cruz

The rise in theft from fuel platforms in the Gulf mirrors the increase in fuel theft from pipelines and Pemex facilities on the ground. The number of unauthorized taps discovered on fuel lines nearly quintupled between 2011 and 2016.

The theft has cost the Mexican government billions of dollars and is sometimes deadly for the thieves and others at the scene.

Cracking down on fuel theft was one of Lopez Obrador's first security initiatives after taking office in December 2018. The president declared victory in spring 2019, saying his administration had reduced fuel theft by 95% and defeated theives.

That response included deploying troops and federal police to pipelines and other high-theft areas, but that alienated some communities, and security forces have struggled to strike a balance between providing security and allowing the industry to operate. In some areas, violence has risen even as fuel theft declined.

"The military is providing more security to the pipelines, but it will be difficult to provide security to vessels shipping petroleum," Vigil said, noting that government still needs to respond to violence rising throughout Mexico and that the military doesn't have the training or resources to effectively pursue pirates in the Gulf. "I have to assume it's going to become more and more dangerous for Pemex transports [and] transport ships."

Fuel theft on land is not always the work of organized crime. At times, local residents have tapped pipelines to access fuel for their own use or for resale. Stealing fuel and other hardware at sea is harder but still lucrative, meaning it's likely to continue and grow as an area of interest for cartels and other criminal groups.

"Not everybody uses drugs, but everybody uses gas," Vigil said. "It is evolving. It's going to be the wave of the future. There's so much money involved"