Madrid, Sep 6 (IANS) Colombia's notorious drug lord Edgar Vallejo-Guarin, nicknamed 'Beto el Gitano (Beto the Gypsy)', has been arrested in Madrid after being on the run for several years, the Spanish Police have said.

Vallejo-Guarin, for whose arrest the US Justice Department had announced $5 million reward, was detained from a luxury hotel in Madrid on the information from the US Drug Enforcement Administration, EFE news agency reported, citing officials.

In 2001, the US had issued an arrest warrant against the man who is believed to be the boss of one of the most important Colombian cartels smuggling drugs into the US and Europe through Spain.

Vallejo-Guarin is alleged to 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.

Meanwhile, the US announced that it would seek the extradition of Vallejo-Guarin.

In a press release, US envoy to Spain, Eduardo Aguirre, applauded the success of the operation and hailed it as 'a new example of the excellent cooperation' between Spain and the US in security matters.