FARC rebels in Colombia have clashed with government forces in the center of the country, Defense Minister Luis Carlos Villegas said Sunday, as the two sides push to finalize a historic peace deal.

"This took place 48 hours ago in La Uribe. A FARC patrol unit came upon an army rapid response team patrol and engaged," Villegas said.

"There was a number of injured," Villegas said without further details about the injuries. The rebels were offered medical assistance, he said.

And no troops or civilians were injured, an army statement added.

The injured rebels were members of a delegation that was due to travel to the ongoing peace talks being held in Havana.

The violence comes as a discouraging sign while the government and rebels are thought to be close to ending five decades of civil war.

And Carlos Lozada, who serves as a FARC negotiator in the peace process, charged on Twitter that "what happened there was not a clash by patrols bumping into one another."

"This was an attack on FARC delegates who were on their way to Havana," Lozada said, insisting that the army refused to evacuate by air the rebels who were injured, undermining trust at the negotiating table.

The FARC currently has about 7,000 members.

It signed a ceasefire and disarmament arrangement with the government last month at peace talks in Cuba.

The government said it hoped to move on to a full peace deal within weeks.

The Colombian conflict started in the 1960s as a rural uprising for land rights that spawned the communist FARC.

It has left 260,000 people dead, 45,000 missing and nearly seven million displaced, according to official figures.

The rebels signed a unilateral ceasefire in 2015; the government responded by de-escalating the conflict. A bilateral ceasefire only takes effect after the peace deal is signed.