Six hidden burial sites have been discovered by Mexican authorities outside the city, fueling allegations that they may contain the bodies of 43 students who went missing after protestors clashed with local police in the violent state of Guerrero a week ago, which also resulted in six deaths, Mexican officials said Saturday. The students were from a special kind of rural university in the town of Ayotzinapa, near Iguala.

Guerrero is situated on the outskirts of Iguala's poor Pueblo Viejo district, a town about 120 miles south of Mexico city. Guerrero State Prosecutor Inaky Blanco could not confirm the number of bodies that were found and declined to speculate whether the remains belonged to the missing students. However, experts will conduct DNA tests to identify the bodies, the semiofficial National Human Rights Commission said Sunday.

"It would be irresponsible" to jump to conclusions before tests to identify the bodies, Blanco said. The victims were described to have been "savagely slaughtered," Guerrero State Gov. Angel Aguirre added.

"On Sept. 26-27, Iguala city police attacked a group of students rallying to protest against government policies. Six people were killed, more than two dozen injured and more than 50 students vanished. About 15 eventually were found hiding in their homes, but 43 remained missing," the Los Angeles Times reported.

The Aytozinapa Normal school, attended by the missing students, is known for militant and radical protests that often involve hijacking buses and delivery trucks, according to Fox News.

Within days, 22 police officers were arrested for what prosecutors said was the unjustifiable use of excessive force. They are believed to have been penetrated by criminal organizations, at whose behest the police may have been acting.

"If the graves turn out to contain the students, it will suggest they were summarily executed by their captors, be they police or cartel criminals. And if that proves true, it will constitute the most egregious human-rights atrocity in Mexico since President Enrique Pena Nieto took office in late 2012 and one of the worst in recent years," the LA Times reported.

"The suspicion, the hypothesis, is that they are being held by organized crime gangs that operated in collusion with the police," said Vidulfo Rosales, a lawyer for a local human rights group who is assisting the families of the missing students.

An additional eight people have been arrested since the burial site was found, Rosales said, adding that he could not identify them.

Violence is frequent in Guerrero, a southern state where poverty feeds social unrest and drug gangs clash over territory, Fox News reported.

"Mexico cannot let such a serious incident go unpunished," said Tomas Zeron, head of investigations from the federal attorney general's office.

In the past eight years, more than 20,000 people are registered as having disappeared in Mexico. Most of them have never been found.