Three U.S. researchers - including a Minnesota graduate student - are free on bail in Brazil but had to hand over their passports after being jailed on suspicion of illegally prospecting for minerals, federal police say.
The Americans, identified as Mark Andrew Tress, Kelly Michael Wendt and Michael Matthew McGlue, were released late last Thursday night.
Each posted bail of $2,550, handed over his passport and pledged to return for legal proceedings, according to a police spokesman who declined to be identified in line with internal regulations. He did not know their hometowns.
The three were working on a project in southwestern Brazil in conjunction with the University of the State of Sao Paulo, which described them as students from the University of Arizona.
University of Arizona spokesman Johnny Cruz confirmed McGlue and Tress are graduate students in geosciences at the university but said Wendt is not a student there.
In Minnesota, the University of Minnesota in Duluth said Monday that Wendt is a graduate student in the Department of Geological Sciences.
"I'm aware of a team that was detained and released," Cruz said. "The university has been in frequent contact with the students' attorney and families and is providing support that enabled them to be released and to return home as soon as possible."
He said they were "conducting collaborative research" on climate and environmental change in the Pantanal, the world's largest wetlands. The project, he added, involved collecting short sediment cores from the bottom of lakes and wetlands in the Pantanal region.
But the police spokesman said they were suspected of "unauthorized mineral prospecting" and working in Brazil with only a tourist visa.
The University of the State of Sao Paulo said in a statement that two Brazilian scientists were also arrested and later released.
The Brazilian university said the research was authorized by the nation's environmental protection agency and did not involve the extraction of minerals or the illegal collection of flora or fauna. (Copyright 2009 by The Associated Press. All Rights Reserved.)