SOFIA, March 22 (Xinhua) -- Bulgarian authorities have arrested three members of an international organized crime group for drug trafficking from Africa to Western Europe, the Prosecutor's Office said in a statement on Friday.

The three, including one Bulgarian and citizens of Tanzania and Somalia temporarily residing in Bulgaria, were arrested on Tuesday in Sofia on the basis of a European arrest warrant issued by Germany, the statement said.

"The evidence gathered indicates that their function within a large international criminal network was to recruit and send to African countries Bulgarian "mules" to traffic drugs especially to Italy and Germany," the statement said.

A mule usually refers to a person who personally smuggles contraband across borders for a smuggling organization.

The procedure for their extradition to Germany is ongoing, it added.