A week after the governor of a Mexican state, where 43 students disappeared after a day of violence, resigned, the acting governor has said there may be signs the students are alive, according to El Excelsior.

Students protesting from the Ayotzinapa teachers school disappeared on Sept. 27 in Iguala, Guerrero State, when unidentified masked men opened fire on them, killing at least three individuals. A separate incident later that day also resulted in three shooting deaths.

Hitmen admitted killing 17 of them, about two dozen police officers were arrested and soon after a mass grave was unearthed.

The grave had more than two dozen badly burnt bodies, making it hard for authorities to make an immediate identification at the time.

None of the bodies belonged to the students, authorities later found, adding that the hillside in Iguala is littered with graves.

Fellow students of those missing vowed serious action if their classmates were not found, and recently a number of government buildings were burned.

The state prosecutor accused the police chief and mayor, along with the Guerreros Unidos gang.

Acting governor, Rogelio Ortega, said there is no evidence that the remaining kidnapped have been killed, and there are indications they may be alive.

Meanwhile, authorities continue to search for the students and the investigation continues. The latest search zone includes the edge of a municipal rubbish dump, The Guardian reported.

On Tuesday, four new suspects were detained, who admitted direct participation in the disappearance of the students, bringing the total of arrests to 56.

The students still remain missing as the city celebrated the Mexican equivalent of Halloween, or Dia de los Muertos (Day of the Dead), with an unusually somber tone Friday.

Usually residents would fill Iguala's main plazas with fake tombs, but this year, three large black crosses lean against the front steps of the blackened City Hall, Maine Public Broadcasting reported.