RIO DE JANEIRO — Federal police in Brazil have ordered the detention of 12 people who allegedly pledged allegiance to the Islamic State group via social media.

Justice Minister Alexandre de Moraes told journalists in Brasilia on Thursday that 10 had been arrested and two more were being sought.

Moraes says police acted because the group had been discussing the use of weapons and guerrilla tactics to potentially launch an attack during the Olympics, which begin Aug. 5.

The arrests were made in the southern states of Sao Paulo and Parana. Moraes says there were no specific targets for attack.

Last week, Brazil's interim government's top military aide said the concerns with terrorism had "reached a higher level" after the attacks of six days ago in Nice, France.