A group of armed, masked criminals has robbed a second bank this week in Southern Brazil.

The heist in Cametá, Pará state was preceded by a robbery Monday in the city of Criciúma, in Santa Catarina state.

According to police, the robbers were all armed with high-caliber weapons and used explosives to access the two banks. The robbers also grabbed civilians they used as hostages and as human shields.

In the latest robbery, one man was reportedly killed while another was injured. Witnesses at the latest bank robbery had captured footage of the crime, which were uploaded on social media.

Investigators said that the group included at least 20 men. Before they robbed the banks, the group reportedly attacked a military police station to prevent officers from responding.

To access the Cameta bank's vault, the group used an explosive to blow a hole in the side of the building. According to the state governor, Helder Barbalho, the robbers blew up the wrong safe during the second heist and escaped without much money.

The robbers fled the scene before police arrived. They fled in cars, which they then abandoned before riding boats. None of the robbers were caught.

During the first robbery, the group attacked the Bank of Brazil. Workers at the bank were forced to sit in the middle of the street to prevent police from firing as the robbery took place. After the heist, the group scattered money onto the streets. The bank said that about $150,000 was recovered but it did not disclose how much the group had escaped with.

Investigators said that both attacks were likely planned in advance and were well thought out. The group is believed to be composed of people living outside the Santa Catarina and Pará states.

"The [Criciúma] operation was successful for the criminals...That's the truth," Santa Catarina governor Carlos Moisés da Silva admitted during an interview.

Authorities said that they are now conducting an investigation into the robberies and a manhunt operation has been launched to identify and apprehend the culprits.