Liverpool star Luis Diaz's father released by Colombia's ELN two weeks after kidnapping

Bogota: Colombia's National Liberation Army (ELN) guerrillas on Thursday freed the father of Liverpool football star Luis Diaz, after kidnapping him in the country's north nearly two weeks ago, the government said.

The kidnapping of Luis Manuel Diaz has disrupted the government's peace talks with the ELN, which restarted last year in hopes of ending the group's part in Colombia's 60-year conflict, which has killed at least 450,000 people.

The two sides began a six-month ceasefire in August.

Local television channels showed Diaz's father at an airstrip in the city of Valledupar in Colombia's Cesar province after he descended from a helicopter.

The government's negotiating delegation at peace talks with ELN said in a statement it celebrated the liberation and that Diaz was safe and sound, but that the kidnapping "should never have happened."

"The current process with the ELN has advanced like no other until today. Regardless, our delegation considers that the kidnapping of Luis Manuel Diaz has placed our dialogue in a critical situation and because of it, the time has come to take decisions to eliminate kidnapping," the statement said.

All people being held by the ELN must be liberated, the statement added, though it did not give a figure for remaining hostages. Guerrilla groups in Colombia have historically used kidnapping as a fundraising and pressure tactic.

The ELN said a week ago it would free Diaz but his liberation was delayed amid a back-and-forth between the group and the government. The rebels said military operations were impeding liberation efforts, which the army denied.

Diaz and his wife Cilenis Marulanda were taken by armed men as they were driving in La Guajira province. Marulanda was freed within hours.

The government is trying to conduct negotiations with various armed groups, but discussions with the ELN are the most advanced.

In September Reuters exclusively reported that Colombian security sources expect that at least 40% of ELN fighters could reject a potential peace deal and remain armed.

The atomized command structure of the ELN has long been a concern for security analysts and critics of the talks, who have warned the group's most radical units are unlikely to adhere to an accord.