The Tohono O’odham Police Department and a federal joint task force have busted a major drug- and human-trafficking ring, leading to a dozen arrests.

The ring, which smuggled more than 1,300 pounds of marijuana and 120 illegal immigrants a month, was uncovered after a two-month investigation by detectives and federal special agents, according to a news release.

The organization smuggled the marijuana and illegal immigrants through the Tohono O’odham Nation to Tucson. Pauline Grijalva is suspected of laundering about $350,000 in illicit proceeds through financial institutions during the past three years, the release said.

Seven other U.S. citizens and four undocumented Mexican nationals also were arrested, the release said.