A Venezuelan Gang Is Expanding Its Deadly Reach to the U.S.

“Please don’t tell me you’ve seen them,” Salisbury responded.

In fact, the colleague said, Tren de Aragua members were operating in Texas. Now, Salisbury said, there are also dozens of criminal cases involving the gang in Miami, where he is based.

“They expanded fast in Latin America,” he said, “and they’re expanding fast here.”

Founded in a Venezuelan prison where it ran a zoo, swimming pool, disco, restaurant and bar, the Tren de Aragua has grown into a fearsome transnational criminal force in less than a decade—“MS-13 on steroids,” as one federal official put it, referring to the Central American gang that is entrenched in many U.S. communities. The specter of crime caused by immigrants has become a major theme in the presidential campaign, with former President Donald Trump calling out “migrant crime” repeatedly.

Federal crime data show homicides and other crimes have dropped—and that the U.S. is far safer than it used to be. The gang isn’t a household name, but its activities are a source of fascination on social media. “I think the Tren de Aragua in the U.S. could help elect Trump,” said Michael Shifter, a senior fellow at the Inter-American Dialogue think tank in Washington.

Just as the Italian mafia followed the 19th century wave of immigration to the U.S., Tren de Aragua has emigrated alongside nearly eight million Venezuelans fleeing the reign of strongman Nicolás Maduro. Everywhere Tren de Aragua has set up, investigators say, it has established drug-distribution networks, extortion rackets and prostitution rings, preying on Venezuelans as they make new homes elsewhere in Latin America. 

American officials fear the same pattern emerging in the U.S., where more than 700,000 Venezuelans have settled in the past four years. Tren de Aragua members are suspects in the shooting of two New York police officers, the killing of a former Venezuelan police officer in South Florida, and crimes from Chicago to Texas, law-enforcement authorities said.

In all, there are now more than 100 investigations in the U.S. involving suspected members of Tren de Aragua, said a high-ranking Immigration and Customs Enforcement official.

The Treasury Department imposed sanctions on the group in July, and the State Department has offered up to $12 million as a reward for information leading to the arrest of three of the group’s leaders.

The Tren de Aragua—which means the Train of Aragua, the Venezuelan state in the center of the country—first relocated to neighboring Colombia before putting down roots in Peru, Chile, Ecuador and other countries, law-enforcement authorities and crime researchers say. The gang is looking for better opportunities than those in Venezuela, where the economy has capsized under Maduro’s rule, leading to hyperinflation and poverty made worse by U.S. sanctions.

Tren de Aragua members have found particularly lucrative territory in New York City, authorities said. They are accused of robberies at Macy’s, Sunglass Hut and upscale stores, and moped-riding gang members also have been blamed for snatching phones from unsuspecting pedestrians, said Joseph Kenny, chief of detectives for the New York Police Department.

“It was like a wave of crime like we had never seen before,” Kenny said. “They can come here and make their money very quickly.”

Members sport tattoos, favoring depictions of a train, the No. 23 worn by NBA legend Michael Jordan and the Nike swoosh. They peddle drugs along Queens’ bustling Roosevelt Avenue but don’t extort small Venezuelan businesses like they do elsewhere, Kenny said.

“They don’t have to nickel and dime a mom-and-pop store for five dollars a week for protection when they can walk into Macy’s and steal $7,000 worth of clothing and resell it out on the street,” he said.

Tren de Aragua members are difficult to identify and track because they have entered the U.S. through the southern border and share migration paperwork among themselves, Kenny said. It is difficult for police to determine a suspect’s criminal history because the U.S. doesn’t have diplomatic ties with Venezuela.

“They could be wanted for murder in Venezuela,” Kenny said. “We wouldn’t know that.”

Tren de Aragua expanded quickly from its origins in Venezuela’s Tocorón prison, trafficking drugs, contracting hits and extorting businesses outside the penitentiary walls—activities allowed by Venezuelan prison authorities, law-enforcement officials said.

Venezuelan government officials didn’t respond to requests for comment. Foreign Minister Yván Gil this year called Tren de Aragua a figment of the media’s imagination.

The group branched into neighboring Colombia around 2018, setting up in the teeming working-class neighborhoods of Bogotá’s south side, where gangs battle it out to sell drugs, run bordellos and demand a monthly “vaccine,” or protection payment, from businesses, investigators say. Soon Tren de Aragua was dismembering rivals, leaving the remains in garbage bags on the streets.

Selling cocaine, marijuana and a potent cocaine derivative called bazuco is the gang’s main business. It also extorts businesses, killing the employees of stores whose owners don’t pay up.

One recent afternoon, German Murillo, a businessman organizing other store owners in Bogotá to report Tren de Aragua activities, sat in a cafe in front of a supermarket that the group targeted last year. When the owner refused to pay the “vaccine,” a gunman fatally shot a worker from behind as he arranged produce.

“They extort restaurants, small shops, anyone,” Murillo said. “It’s an organization that’s involved in everything.”

Tren de Aragua found an inviting environment in Chile, known for its relative affluence and low crime.

“The gang looks for earnings,” said Ronna Rísquez, a Venezuelan journalist and author of a book on Tren de Aragua. “In Chile, there were possibilities.”

Chile didn’t have powerful drug gangs, leaving the field wide open for Tren de Aragua. The gang’s methods have shocked Chilean officials.

Carolina Tohá, Chile’s interior minister, described how the gang carries heavy weaponry, shows special cruelty when settling scores, and commits crimes authorities hadn’t seen in the past. In February, the Tren de Aragua kidnapped a Venezuelan dissident from his apartment and killed him. His body was found in a suitcase buried under more than 4 feet of concrete in a nearby shantytown.

“It has been a very shocking experience for Chilean society,” Tohá said. 

Chilean officials attribute a 31% rise in homicides since 2019 to increased gang activity. Kidnappings have more than doubled in the past decade, authorities said. The number of foreign victims and perpetrators of homicides—many of them Venezuelans—have risen rapidly, crime statistics show.

Authorities in Chile tracked down one of Tren de Aragua’s founders, Larry Álvarez, to Santiago, where he had been operating a Venezuelan restaurant four blocks from the presidential palace since 2018. 

Though he appeared to be making an honest living like other Venezuelans in Chile, Álvarez was actually committing crimes, including a homicide, researchers and investigators said. When his cover was blown, Álvarez fled to Colombia.

From a farm in the prosperous coffee belt, Álvarez, better known as Larry Changa, continued to direct drug trafficking in Chile, Colombian prosecutors said. Police recently arrested him, and he is in jail awaiting extradition to Chile. Álvarez declined to comment.

Prosecutors said Tren de Aragua is trying to challenge Colombia’s most powerful armed militia, the Gulf Clan, which traffics cocaine and migrants to the U.S. and smuggles metals from illegal mining. Tren de Aragua is now dabbling in both moving migrants and extracting illegally mined gold.

“It’s a certainty that the Tren has expanded,” one of the prosecutors said, “and they have a big market for narco-trafficking in the U.S.”

Ryan Dube and Michelle Hackman contributed to this article.

Write to Juan Forero at juan.forero@wsj.com