Former presidential candidate Ingrid Betancourt (photo released by the Colombia's government, Nov 2007)

Colombia's ombudsman says former presidential candidate Ingrid Betancourt, who has been held hostage by FARC rebels for six years, is seriously ill with hepatitis B and malnutrition and is in a very delicate state of health.

Ombudsman Volmar Perez tells Colombia's Caracol Radio his office has received reports that Betancourt has become so ill that her rebel captors sought medical attention for her last month in southeastern Colombia. Perez also says his office has been told that Betancourt is suffering from leishmaniasis, a parasitic skin disease caused by insect bites.

The French-Colombian Betancourt was kidnapped in February 2002 while campaigning for the Colombian presidency. Both the French and Venezuelan governments have become involved in efforts to win her release.

Concerns about Betancourt's health began to grow following the release of a video in which she appeared gaunt and depressed. Authorities seized the video late last year during an arrest of suspected FARC rebels.

The FARC is holding at least 700 people in secret jungle camps for ransom or political leverage. Three Americans are among the hostages. The United States, European Union and Colombian government have designated the FARC as a terrorist organization.

Some information for this report was provided by AFP and Reuters.