Mexico City, Mexico (CNN) -- A day after attacks on two police stations that resulted in the deaths of four police officers in the northern state of Nuevo Leon, a police spokesman vowed Thursday that security will be beefed up in the municipalities and strategies to fight organized crime will be reconsidered.
"We are on permanent alert because the idea and philosophy that we have taken is to continue cleaning up this process of violence in the state," Jorge Domene Zambrano told reporters.
After a meeting of the security cabinet of Nuevo Leon, which was attended by representatives of the attorney general of the republic, the federal police, the Center of Investigation and National Security and the fourth and seventh military zones, the spokesman noted that crime-fighting strategies were being reviewed.
Security measures will be strengthened in the municipal bodies with support from federal and state forces, especially in Monterrey -- the state capital -- and the municipal suburb of Guadalupe, he said.
The municipalities are being urged to reinforce their installations, with strategies being considered to focus on specific sectors, he said.
One attack was directed at the police barracks in Monterrey, where Jose Carrion Galvan and Raul Sergio Salinas Bosque were killed, as was Dr. Jesus Sanchez Barajas. In the other attack, in Guadalupe, officers Santos Munoz Serna and Jose Guadalupe Tovar Martinez were killed, Domene Zambrano said.
No one had been arrested, and the two attacks had not been linked, the spokesman said.
The officers from Guadalupe had clean records and there was no indication either man had been involved in organized crime, he said.
In northeast Mexico, the Zetas have been in a fight with the Gulf Cartel over control of the drug trade in Tamaulipas and Nuevo Leon, including the city of Monterrey.
In a separate incident, police officers responding to a report of a robbery in the area of Vista Hermosa in the municipality of China in Nuevo Leon came across three vehicles carrying weapons, the federal secretary of public security said.
CNN Mexico contributed to this report.