More than 50 alleged members of the feared Zetas drug cartel, including two active duty policemen, women and children, were arrested in northern Mexico, officials said Wednesday.

The arrests came on the heels of the indictment Tuesday of the man believed to be the gang's second in command, Miguel Angel Trevino Morales, along with 13 others in the United for money laundering, accused of hiding millions of dollars of drug proceeds in a horse racing and breeding operation.

But Mexican authorities ruled out a direct link between the raids in Mexico and the United States.

In the northern Mexican state of Nuevo Leon, which borders the United States, security spokesman Jorge Domene said 52 people, including eight women and five children, were arrested there under various operations that began on June 8.

The suspects "held different roles for the criminal group, from leaders of local cells to assassins and spies," Domene told a press conference.

Nuevo Leon is considered among the Mexican states with the biggest presence of Zetas, founded in the 1990s by deserters from the Mexican special forces hired as hitmen for the powerful Gulf cartel, by then boss Osiel Cardenas Guillen.

More than 50,000 people have been killed since President Felipe Calderon launched a tough military crackdown on criminal groups in December 2006, most in battles between rival cartels.