Popular Mexican Governor Candidate Assassinated

Gunmen believed to be from a drug cartel have assassinated a leading politician running for governor in Mexico's Tamaulipas state. Rodolfo Torre Cantu, his campaign chief, his chief of staff, and at least one bodyguard were killed when their convoy was ambushed en route to an election rally, the Wall Street Journal reports. The assassination—the highest profile killing in Mexico in 16 years—is being viewed as a major escalation in Mexico's drug war.

"This is a direct challenge to the Mexican state," said a deputy in Torres' Institutional Revolutionary Party. "This is an armed group trying to tell Mexicans who we can and can't elect." Torres had been expected to easily win the election. Twelve Mexican states are due to elect new governors Sunday, and the government is promising that elections will go ahead as scheduled.