Sept. 6 (UPI) -- Mexican investigators said Thursday they found a mass grave in the state of Veracruz that contained at least 166 human skulls.
In a statement, Veracruz Attorney General Jorge Winckler Ortiz said body parts and clothes were also found in the mass grave, but skulls were counted to determine the most accurate number of how many people were buried there.
Winckler said the human remains appear to have been buried there for two years, but did not give details on how or who was responsible for the burial site. He said his office is committed to identifying the remains.
The area is a known hot spot for drug cartels, which have been suspected of using mass graves before. Over the last few years, there have been numerous examples of mass graves found throughout Mexico.
In March, at least 250 human heads were found in a mass grave in Veracruz.
In 2016, more than 100 bodies were found in a grave in the Mexican state of Morelos.
Last year, Mexico's murder rate increased by 27 percent.