IN THE last days of Álvaro Uribe’s presidency in 2010, Colombia accused neighbouring Venezuela of letting the FARC and ELN, the two main leftist guerrilla groups, maintain camps along its border. In response Hugo Chávez, Venezuela’s president, recalled his ambassador and skipped the inauguration of Mr Uribe’s successor, Juan Manuel Santos. Once Mr Santos took over, however, Colombian officials stopped discussing the camps in public. Most observers concluded that Mr Santos thought Venezuela would respond better to private pleading than to public scolding.

A recent report by the New Rainbow Corporation, a think-tank in Bogotá, suggests Mr Santos’s decision may have partly paid off. Though it is unclear whether Mr Chávez’s government has forced the FARC to leave or simply convinced them, they have moved many camps back to the Colombian side of the 2,000km (1,250-mile) border. Their highest-ranking leaders, Rodrigo Londoño (known as “Timochenko”) and Luciano Marín Arango (“Iván Márquez”), are thought to hop back and forth between the countries. The report also found that the guerrillas are only “minor players” in shipping cocaine. Their role is to protect coca crops—with both the FARC and ELN established in the Catatumbo region of the Norte de Santander department, and the ELN in the north of Colombia’s Arauca department and the south of Venezuela’s Apure state.

Unfortunately, according to the report, the drug and contraband trades have been taken over by international gangs. Venezuela has become the main transit point for Colombian cocaine headed for the United States and Europe. Because of Venezuela’s price controls on fuel—a litre of petrol costs two American cents in Venezuela, compared with up to $1.30 in Colombia—smuggling is another lucrative business. Such opportunities have lured the Zetas, a violent Mexican mob, who have teamed up with a Colombian outfit called the Rastrojos. Together they control much of Colombia’s La Guajira department and Venezuela’s Zulia state.

Echoing a series of recent allegations tying Venezuela’s army to drug gangs, New Rainbow cited reports of the country’s generals aiding traffickers. But the overall picture is one of anarchy rather than of state complicity. “Neither the Colombian government nor the Venezuelan government really has any control over what is happening on the border,” says Ariel Ávila, the report’s lead author. “It is under the control of bandits.”