Police in southern Mexico shot and wounded a German university student in a reported case of mistaken identity, prosecutors said Monday.

His school, the Monterrey Institute of Technology, said in a Twitter post that he was in stable condition and expected to recover, though it did not release his name.

The man was in a van with other students — two Germans, two French and six Mexicans — traveling back from Acapulco and it was passing through the Guerrero state capital of Chilpancingo just after a confrontation between police and kidnappers that killed one officer.

Police tried to stop the van, believing it was suspicious, and opened fire when the students kept driving, fearing that armed men might be trying to kidnap them, state prosecutor Inaky Blanco said.

The German student was shot in the buttocks.

The police involved have been detained and their weapons are being tested, according to a statement from the state attorney general's office.

The shooting came two weeks after police in another Guerrero city, Iguala, opened fire on teacher's college students, killing six and leaving 43 other missing. They have not been found, though 26 officers from Iguala have been detained and officials are attempting to determine is any of the students are in 10 newly discovered mass graves.

The Sept. 26 confrontation in Iguala shed light on a widespread problem with local police in Mexico: They are often linked to organized crime. In the case of Iguala, the police who attacked the students were working with the local cartel, Guerreros Unidos, according to testimony of those arrested.