Two senior officials from the local government of Monterrey were kidnapped within 24 hours, authorities said Monday, the latest sign of deteriorating security in Mexico’s most affluent city.

The northern industrial hub was until recently relatively free of the drug-trafficking violence engulfing other parts of Mexico. But warfare between gangs is now taking its toll in Monterrey and its tony suburbs.

Both kidnapped officials ran the city’s transportation department, which controls roadways, truck routes and car registrations, a division that would make a desirable asset in a drug lord’s empire.

Heavily armed gunmen used vehicles to barge through the front gates of the home of Enrique Barrios Rodriguez, city transportation secretary, about 3 a.m. Monday, officials said. The assailants seized Barrios and bundled him out of his Elite Hills neighborhood.

Residents told reporters that the electricity on the street went out shortly before the abduction.

About 24 hours earlier, Reynaldo Ramos, operations chief of the department, was snatched from his home not far from where Barrios lived.

Mayor Fernando Larrazabal said he did not think either man had received specific threats.

“All we know is … they were taken from their houses by people not yet identified,” Larrazabal said at an impromptu news conference outside City Hall. “Given the gravity of this case, the state prosecutor’s office is handling the investigation.”

The mayor said both officials had drivers but no bodyguards. He would not say why security for Barrios, a former federal congressman, was not stepped up after the abduction of Ramos.

Outside Barrios’ home, pieces of an electric garage door could be seen, toppled on the ground, and people thought to be his relatives were packing up and leaving. The kidnappers also took Barrios’ SUV and a BMW.

Monterrey, capital of Nuevo Leon state, was traditionally relatively quiet in part because top drug traffickers parked their families there, taking advantage of the city’s top schools and hospitals. But as the notorious Zetas gang fights to challenge the dominance of its onetime patron, the Gulf cartel, gun battles, kidnappings and other violence have spread.

In the first 4 1/2 months of this year, as many people were killed around Monterrey as in the two previous years combined.

wilkinson@latimes.com