Madrid  - Edgar Vallejo Guarin, nicknamed "Beto el Gitano (Beto the Gypsy)" and one of Colombia's most-wanted cocain bosses, has been arrested in Madrid, Spanish police said Friday.

He was detained in a luxury hotel after being on the run for years, with the United States having offered a reward of five million dollars for information leading to his arrest.

He is alleged to have organised the smuggling of dozens of tons of cocain into the United States and Europe, to have been responsible for several murders, and is also accused of bribery and money-laundering.

Police sources said he was believed to have gone underground in Venezuela under a false name, and then to have acquired a residence permit for Spain, where he had a home outside Barcelona. The United States intended seeking his extradition, Spanish police said. (dpa)