Updated

Human Rights Watch says illegal armed groups have forcibly disappeared scores if not hundreds of people in Colombia's main Pacific port of Buenaventura in the past two years, killing and dismembering some in so-called "chop-up houses."

The advocacy group's Americas director, Jose Miguel Vivanco, said Thursday the situation is among the most alarming it has seen in years of working in the region.

HRW says the city of nearly half a million people has become Colombia's main source of internal refugees and largely blames criminal bands that include ex-far-right paramilitaries.

Colombian officials say they have investigated several so-called "chop-up houses" and the state ombudsman's office reported at least eight cases of dismemberments over five months last year.

HRW says at least 13,000 people were forcibly displaced from Buenaventura last year.