BOGOTA (Reuters) -Guerrillas from Colombia's National Liberation Army (ELN) rebels are responsible for kidnapping the parents of Liverpool football player Luis Diaz last weekend, the government said in a statement on Thursday.
The incident could threaten ongoing peace talks between the ELN and the government, which restarted last year in hopes of ending the group's part in the country's 60-year conflict, which has killed at least 450,000 people.
The government and the ELN began a six-month ceasefire in August as part of talks.
Interior Minister Luis Fernando Velasco said the situation was "very serious."
"This is a violation of the ceasefire and (...) of course it puts the process at risk," Velasco told journalists.
"We remind the ELN that kidnapping is criminal, violates international humanitarian law and that its duty in building the peace process is not just to stop (kidnapping) but to eliminate it forever," Otty Patino, head of the government's peace delegation, said the statement, adding the father of Diaz should be freed immediately.
Diaz's mother Cilenis Marulanda and father Luis Manuel Diaz were kidnapped by armed men as they were driving in the northern province of La Guajira, officials reported late on Saturday.
While Marulanda was freed a few hours later, the football player's father remains missing.
"We are looking into the issue," an ELN spokesperson said.
The ELN, Colombia's most radical leftist guerrilla group, has long funded its operations with kidnapping, as well as extortion and drug trafficking, according to security sources.
(Reporting by Luis Jaime Acosta and Oliver GriffinWriting by Oliver GriffinEditing by Alistair Bell and Diane Craft)