Brazil arrested 10 people Thursday, believed to be belonging to ISIS, in connection with a poorly organized plot of terror targeting next month's Olympic games in Rio.<br />The group described as "absolutely amateur" by Justice Minister Alexandre Moraes were all Brazilian citizens and in contact via messaging apps such as WhatsApp and Telegram.<br />Federal police are monitoring about 100 people for possible links to terrorist groups, mostly in the porous tri-border region with Paraguay and Argentina, a presidential aide said on Thursday.<br />Brazilian police and intelligence services have been cooperating with French, German, British, Israeli and U.S. intelligence agencies regarding the arrests, the aide said.