Colombian authorities have captured a leading member of the National Liberation Army (ELN), the country's only remaining active guerrilla group, prosecutors said Thursday.

Rafael Antonio Botero, alias Ivan, is suspected of forcefully recruiting 97 children and of organizing a bomb attack which killed six police officers in the northern port city of Barranquilla on Jan. 27.Botero was captured three days after prosecutors ordered the arrest of 21 ELN leaders and other members. Colombia says some of them are in Venezuela and plan attacks from there.

Defense Minister Luis Carlos Villegas said on Thursday that he had discussed the subject with his Venezuelan counterpart Vladimir Padrino over the phone, and that the two might meet somewhere near the border.

Villegas said he did not exclude a meeting between Colombian representatives and Venezuelan President Nicolas Maduro, in an apparent attempt to reduce tension after Venezuela's attorney general accused Colombia of planning to bomb his country.

ELN is Colombia's last active rebel group after the much bigger FARC signed a peace deal with the government in November 2016. The government suspended peace talks with ELN in January when it resumed attacks immediately after completing a three-month ceasefire.