SAO PAULO, Brazil (AP) – A former Brazilian police officer and his son have been arrested in last month’s slaying of a former professor at the University of Maine at Farmington James Petersen in a rainforest town near the Amazon River, local media reported.

Ronaldo Costa dos Santos, 45, and his son Rodolfo Romerito, 19, were found hiding Saturday morning in a small farm near the city of Manaus, about 1,620 miles northwest of Sao Paulo, police investigator Lazaro Ramos told the Folha Online Web site.

They were charged in the Aug. 13 shooting death of Petersen, the 51-year-old chairman of the University of Vermont’s anthropology department who was in Brazil researching the pre-colonial life of native tribes.

Petersen founded the Archaeology Research Center at the University of Maine at Farmington. He taught there for 14 years before leaving for Vermont in 1997.

Three other suspects arrested shortly after the crime accused Santos and Romerito of leading the gang that shot Petersen during a robbery in a restaurant in Iranduba, an Amazon town about 15 miles from Manaus.

Romerito and Santos, a former Amazonas state police officer, did not resist the arrest. Authorities did not immediately say whether they denied involvement in the shooting.