A reporter accompanying a humanitarian mission to release four hostages held by Colombian rebels says the military has interferred with and delayed the handover.

Jorge Enrique Botero says the International Red Cross mission — in a loaned Brazilian military helicopter — has been hounded by military overflights.

Botero spoke live with the Venezuelan television network Telesur from a jungle clearing where he said the handover was about to occur on Sunday afternoon.

He said the group hoped to make it to the lowland provincial capital of Villavicencio by sundown.

Also speaking with Telesur was the guerrilla commander in charge of the handover. He says Colombia's military killed a rebel in his unit in combat on Sunday morning.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

BOGOTA, Colombia (AP) — The International Red Cross says a helicopter has departed to pick up four hostages that Colombia's leftist rebels promised to free.

Three police officers and a soldier are among six hostages the Revolutionary Armed Forces of Colombia says it is freeing unilaterally.

The police and soldier have been held for two years or less. The two politicians set to be released Monday and Wednesday have been held far longer.

The Red Cross says those picked up Sunday will be flown to the provincial capital of Villavicencio in Colombia's eastern lowlands.

The unilateral releases are the guerrillas' first in nearly a year, but analysts say chances for a peace dialogue with Colombia's government are far off.