BOGOTA (Reuters) - The release of Liverpool footballer Luis Diaz's father by Colombian rebel group the National Liberation Army (ELN) will be delayed while military operations continue in the region, the group said.

Diaz's mother Cilenis Marulanda and father Luis Manuel Diaz were taken by armed men as they were driving in La Guajira province on Oct. 28. Marulanda was freed within hours.

The reason why they were snatched is not immediately clear, but security sources say the ELN, Colombia's most radical leftist guerrilla group, has long funded its operations with kidnapping, as well as extortion and drug trafficking.

Although the ELN has said the soccer player's father would be freed "as soon as possible", the presence of Colombia's security forces in the region have hampered his release, the group said in a statement late on Sunday.

"The area is still militarized, there are flyovers, deployment of troops, megaphone broadcasts, offers of rewards and an intense combing operation," the statement said, adding that these conditions have not permitted the release of Luis Manuel Diaz.

"If operations continue in the area, the release will be delayed and risks will increase," the statement said.

Colombia's government reported the ELN was responsible for the kidnapping last week.

The rebel group and the government are currently engaged in a ceasefire amid peace talks looking to end the ELN's role in Colombia's six-decade internal armed conflict, which has left at least 450,000 dead.

Interior Minister Luis Fernando Velasco said last Thursday that the situation was "very serious" and that it violated the ceasefire agreement.

(Reporting by Oliver Griffin; Editing by Alison Williams)