BOGOTA, Colombia (AP) — Colombia’s government said Thursday that the guerrilla group National Liberation Army, known as ELN, was responsible for the weekend kidnapping of the father of Liverpool and Colombian national soccer team striker Luis Díaz.

The peace delegation of the government, which is currently in negotiations with ELN, said in a statement it was “officially aware” that the kidnapping had been “perpetrated by a unit that belongs to ELN.”

“We demand that the ELN releases immediately Mr. Luis Manuel Díaz and we say as of now that they are entirely responsible to secure his life and integrity,” said Otty Patiño, who leads the peace delegation.

Both parents of Liverpool’s Díaz were kidnapped by armed men on motorcycles on Saturday at a gas station in the small town of Barrancas. The footballer’s mother, Cilenis Marulanda, was rescued within hours by police who set up roadblocks around the town of 40,000 people, which is near Colombia’s border with Venezuela.

Díaz’s father remained missing, which triggered special forces to search for him in a mountain range that straddles both countries and is covered by cloud forest. Police also offered a $48,000 reward for information leading to Diaz’s father.

Díaz is one of the most talented players on Colombia’s national team and currently plays for Liverpool in the English Premier League, which he joined last year in a deal worth $67 million.

The 26-year-old striker was absent from Liverpool’s match against Nottingham Forest on Sunday. Díaz’s teammates expressed their solidarity with the Colombian by holding up one of his jerseys on the pitch after scoring the team’s first goal in their 3-0 victory.