LOS ANGELES - FBI agents have arrested a Mexican prosecutor suspected of involvement in the production and trafficking of illegal drugs including heroin and cocaine into the United States, authorities said Wednesday.

Edgar Veytia, the attorney general in Mexico's western state of Nayarit, was arrested Monday at the US border in San Diego. He was detained on a warrant from a New York state court.

Veytia was believed to have been detained on the bridge between San Diego and the Tijuana airport, local media reported.

"This is a development that we were not expecting," Nayarit Governor Roberto Sandoval said without addressing the alleged high-level crime.

In the US indictment seen by AFP, prosecutors said Veytia is facing three counts: conspiracy to produce and distribute heroin, cocaine, methamphetamine and marijuana, conspiracy to import those substances into the US, and conspiracy to distribute them.

The indictment said he engaged in drug activity from January 2013 until last month. One of his aliases was Diablo, or devil, according to the indictment. It said the amounts of drugs involved were at least one kilo of heroin, five kilos of cocaine, 500 grams of methamphetamine and 1,000 kilos of marijuana.

Nayarit is on Mexico's Pacific north coast and shares a border with the states of Jalisco and Sinaloa, where drug cartels are powerful. Some Mexican officials have faced trial for drug trafficking in the United States, including Mario Villanueva, former governor of the state of Quintana Roo on the Caribbean coast.

Mexico is the scene of brutal violence linked to drug trafficking. Since the government deployed the army to fight drug cartels in 2006, more than 170,000 people have been killed and 28,000 have gone missing.

Recently discovered mass graves in the eastern state of Veracruz -- another state where the Jalisco New Generation cartel is seeking dominance -- contained at least 242 bodies, according to investigators.-AFP