Eleven oil workers kidnapped last month in Colombia‘s northeast were released by the ELN guerrilla gorup, according to reports, following calls from the rebels for a “social tax” on oil extraction in the country.

The 11 (pictured above), who had been working on the Bicentennial Pipeline in the department of Arauca, were handed over to a humanitarian delegation on Tuesday. They had been kidnapped on February 28 by members of the National Liberation Army’s (ELN) Domingo Lain Font, reported El Pais. The number of victims was originally reported to be nine.

On Monday, the ELN posted a statement on its website saying that it would reconsider its “offensive against oil infrastructure” if the government complied with six demands, including imposing a “social tax” of $10 per barrel of oil extracted in Colombia. This should be paid by multinationals and handed directly to communities affected by extraction, the group said.

InSight Crime Analysis

The news that the ELN were behind the kidnappings is not a surprise, as the other guerrilla group active in the area, the Revolutionary Armed Forces of Colombia (FARC), recently declared that they would cease kidnapping civilians.

The ELN are relatively small players in kidnapping in Colombia, accounting for roughly 10 percent of all cases last year, compared to the FARC’s 26 percent. The fact that they are not deeply involved in the business makes their offer to cease targeting oil companies more credible, as kidnapping oil workers constitutes only a fraction of their group’s finances.

Despite the ELN’s resurgence in recent months following its dip over the last decade, it has long had its sights set on peace negotiations, perhaps more so than the larger FARC. Though it is unlikely the government will impose the proposed social tax on oil, the ELN’s offer to cease attacks does not necessarily ring hollow.