BOGOTA, Colombia — A Cuban man arrested in Colombia for allegedly plotting to kill American diplomats in the name of Islamic State says he was actually part of a right-wing underground cell that sought to attack leftist politicians.

Raul Gutierrez offered no evidence to back his claim in an interview with W Radio on Thursday and even struggled to identify one of his supposed targets, presidential candidate Gustavo Petro. But Colombia's chief prosecutor nonetheless ordered he be interviewed about the claims and asked the government to boost security for Petro and former rebel leader Rodrigo Londono.

Gutierrez was arrested in March after Spanish authorities, the FBI and Colombian police uncovered evidence that he intended to stockpile explosives at the urging of radical Islamic groups. He pleaded not guilty.