Tax authorities in Colombia have apologised for demanding a tax return from a woman politician held captive by Marxist rebels for almost three years.

Ingrid Betancourt, 42, was seized by Revolutionary Armed Forces of Colombia (Farc) rebels in February 2002 while campaigning for the presidency.

She has been held captive in a secret jungle jail ever since.

Tax officials described a letter posted to Ms Betancourt asking for her to file a tax return as "an unwitting error".

The letter asked Ms Betancourt, who is a dual Colombian and French national, to disclose her financial affairs for the year 2003.

But the tax department insisted the letter had been sent as part of a nationwide drive to prompt payments, and that Ms Betancourt had not been directly targeted.

"It was a lamentable error and for that reason we offer our apologies to Ms Betancourt's family," said Mario Aranguren, director of the Colombian tax department.

"It was an unwitting error in a mass mail drop," the department added in a statement.

"As is public knowledge, she has been kidnapped and so cannot be required to pay her taxes."

Kidnapping rife

Because of the high numbers of kidnappings in Colombia, the government has instructed financial authorities not to tax people held hostage.

They have also asked employers to continue paying their wages.

Ms Betancourt was snatched by Farc rebels while at a roadblock.

The rebels want to swap Ms Betancourt and 71 other hostages for guerrilla fighters held in government prisons.

According to the Colombian government Farc currently holds around 1,600 hostages, including around 20 politicians, 47 army officers and three Americans.