Colombian rebels kill 3, including senator

Daniels was serving as an intermediary to negotiate the release of hostages when she was killed.

BOGOTA, Colombia (CNN) -- Colombian government officials said Sunday they suspect members of a rebel group are responsible for the execution-style killings of three people, including a senator, whose bodies were found over the weekend.

The bodies of Sen. Martha Catalina Daniels, her chauffeur and bodyguard, Carlos Lozano, and her friend, Ana Maria Medina, whose husband is being held by the rebel group, were found off a country road near Zipacon, Daniels' home district 25 miles west of the capital, police said.

Each had been shot twice in the head, and their bodies showed signs of torture, said police Cmdr. Alvaro Sandoval. The bodies were taken to Bogota for a forensic investigation.

Authorities say Daniels, a member of the Liberal opposition party, was serving as an intermediary to negotiate the release of hostages. The three had been missing since early Saturday, when they left together in Daniels' Mercedes Benz truck for an undisclosed destination, unaccompanied by a security contingent. Daniels had called for a security escort at 8 a.m. local time Saturday, but the group set out three hours earlier.

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Colombia's attorney general, Louis Camillo Osorio, told reporters that all indications pointed to an assassination by the Armed Revolutionary Forces of Colombia rebel group, also known as FARC.

There was no immediate claim of responsibility for the killings.

FARC, Colombia's largest rebel group, has been locked in confrontation with the Colombian military since February 21, when President Andres Pastrana broke off peace talks and ordered the military to re-take a safe haven the rebel group had been operating in for three years, in the southern part of the country.

Pastrana's orders came after FARC rebels hijacked a commercial airliner carrying Sen. Jorge Eduardo Gechen, chairman of the Colombian Senate's peace commission. He and five senators are being held captive by FARC, which has demanded the release of some 200 rebels being held by the Colombian government.

The killings also come a week before national congressional elections and less than three months before the presidential election.

On February 23, presidential candidate Ingrid Betancourt was kidnapped by FARC, which offered to exchange her and others it holds captive for the release of government-held prisoners. The government rejected the offer.

-- CNN en Espaņol Correspondent Fernando Ramos contributed to this report.