efe-epaRio de Janeiro

Three suspects were killed and two others arrested Monday when dozens of gunmen who carried out a robbery in Paraguay fled into neighboring Brazil and clashed with police, Brazilian authorities said.

The shootouts took place in the towns of São Miguel do Iguaçu and Itaipulandia as Brazilian police pursued the robbers, believed to be members of the Brazil-based criminal organization known as the PCC.

The assailants were reported to have made off with some $40 million in cash from the offices of a security company in Ciudad del Este, Paraguay.

One suspect was arrested while trying to board a bus for Sao Paulo, Brazilian Federal Police said.

Authorities seized a total of five motor vehicles, a boat, two guns, a large amount of ammunition, and seven kilos of explosives.

Brazil's president, Michel Temer, ordered the Justice Ministry and Federal Police to collaborate with Paraguayan authorities on the robbery, his office said in a statement.

The first encounter between the gunmen and Brazilian cops took place in Itaipulandia, where around a dozen of the robbers came ashore after crossing the Itaipu dam reservoir in a boat.

That contingent managed to escape after trading shots with the police.

The major confrontation unfolded later in São Miguel do Iguaçu.

Paraguayan police said that as many as 60 PCC members took part in the pre-dawn assault on the Ciudad del Este office of the Spanish firm Prosegur.

One policeman was killed and four other people, three of them civilians, were wounded on the Paraguayan side of the border, where the attackers also set a score of vehicles on fire to cover their escape.