Ten people were killed Wednesday in a confrontation between police and an armed group in northern Nicaragua, officials said.

According to a National Police statement, the shooting broke out when officers came upon an armed band robbing a grocery store in the town of Bocas de Ayapal in Jinotega state. Six gunmen and four officers died, and two people were wounded, police said.

Such a mass killing is unusual in the country, which has had one of the lowest crime rates in Central America since armed political conflicts in the 1980s.

Local officials contradicted the police version of the shootout in interviews with Nicaraguan television Channel 12.

Janeth Sobalvarro, mayor of nearby San Jose de Bocay, said there was no robbery, but rather was solely a confrontation between police and the gunmen.

Many people in the northern province of Esteli, including Roman Catholic Bishop Juan Abelardo, have said the armed group has organized to fight the leftist government of President Daniel Ortega.

"I think they are minimizing the situation and making a mistake," Abelardo told Channel 12. "These are armed people and you have to meet their demands."

Police and Nicaraguan troops, which were also involved in Wednesday's clash, have described the armed band as common criminals. Ortega's government has not spoken about the group.

The area of the shootout was a stronghold for the Contra rebels who fought the Ortega-led Sandinista movement in the 1980s.

Sandinistas overthrew dictator Anastasio Somoza in 1979 and Ortega's new government withstood a concerted effort by the U.S.-supported Contras to oust him.

Ortega was elected president in 1984 but was defeated after one term. Since returning to power in a 2007 election, he has boosted his popularity and now is seeking to remove an article in Nicaragua's constitution intended to ban consecutive presidential terms.

Ortega's critics say that he wants to become president for life and that his government has become authoritarian and opaque.