Federal agents in Puerto Rico on Friday arrested three island police officers accused of providing security for drug traffickers

Federal agents in Puerto Rico on Friday arrested three island police officers accused of providing security for drug traffickers, an FBI spokesman said.A fourth officer indicted by a U.S. grand jury remained at large, spokesman Harry Rodriguez said.The U.S. territory police officers, all members of an extradition unit, are among six people indicted on charges including conspiracy and weapons possession related to drug trafficking.Police arrested one of the two suspects who are not police officers, Rodriguez said. The raids took place in and around the Puerto Rican capital of San Juan.The investigation of the drug ring began more than a year ago, Rodriguez said.The island's 8,000-strong police force is reeling from accusations of corruption. In June, federal authorities charged six officers with planting evidence and building false cases against people in a northwest coastal town