Hundreds of primary and secondary schools in the Mexican resort city of Acapulco reopened after being shuttered for more than a month as teachers refused to work amid extortion threats.

Teachers at more than a third of the Pacific port city's 1,270 schools boycotted the first month of classes to press demands for protection from extortionists who were demanding up to 50 percent of their salaries.

Authorities finally agreed to deploy military detachments at schools and 90 percent of Acapulco's educational institutions were open Monday, according to both administrators and representatives of the teachers union.

Ernesto Aguirre Gutierrez, special projects coordinator for the Guerrero state government, said all of the teachers' demands have been met.

Besides the troop deployments, school officials installed 45 security cameras and 170 panic buttons with direct links to the police as well as 100 additional telephone lines, he said.

Despite those steps, members of the small Ceteg teachers organization plan a protest Wednesday in Acapulco to call for greater security.

"The accords signed with the (state) government don't guarantee security, as the pages don't even have official seals on them," one Ceteg leader told Efe, speaking on condition of anonymity.

Guerrero, whose mountains are a prime growing area for marijuana and opium poppies, has been the scene in recent years of a war between rival drug cartels that left 370 people dead last year in Acapulco alone.

Some of the gunmen employed by the cartels as enforcers and security guards have developed lucrative sidelines in kidnapping and protection rackets.