Security forces in Colombia say four hostages have been shot dead by FARC rebels during a rescue attempt.
All four were members of the security forces. They had been held for more than 12 years by the Revolutionary Armed Forces of Colombia.
Defence Minister Juan Carlos Pinzon said they had been shot in the head or back.
He said their bodies were discovered by troops after a fight with rebels. Chains were found alongside them.
President Juan Manuel Santos said the FARC were "solely responsible" for the deaths.
The BBC reports FARC leader Alfonso Cano was killed in combat three weeks ago.
The FARC still hold 14 members of the security forces, as well as dozens of civilians.
Mr Santos has said there can be no peace talks with the rebels until they release all their captives and stop attacks.
The FARC have been fighting to overthrow the Colombian government since the 1960s.