Traffickers have killed an officer from Rio de Janeiro’s police pacification units in the first deadly attack on the elite force, throwing into doubt the community policing model’s ability to keep control of the city’s favelas.

Military police officer Fabiana Aparecida de Souza, of the Nova Brasilia Pacifying Police Unit (UPP) in the Complexo do Alemao neighborhood, died Monday in an attack on a police building by around 10 criminals, Veja reported.

Beginning Tuesday morning, police were sent to reinforce the area, including members of BOPE, an elite special-operations unit. Authorities have identified at least seven suspects, O Dia reported. By the end of Tuesday night, three adults and one teenager had been taken into police custody in connection with the attack.

According to Veja’s report, Rio state governor Sergio Cabral released a statement expressing sympathy for the officer’s family. “The state government believes that marginal groups are losing strength before the policies of public security and that actions like these demonstrate the desperation of criminal organizations,” read an excerpt.

The influx of BOPE officers following the attack may delay the planned occupation of the Jacarezinho favela in Rio’s North Zone in August. This is the city’s third largest favela after Rocinha and Complexo do Alemao.

InSight Crime Analysis

The favela was first occupied by the security forces in November 2010 in a highly-publicized operation, and pacifying police took over Alemao after the military withdrew just under two months ago. That criminal bands in Alemao were bold enough to carry out an attack against police headquarters raises the question of whether the UPP is capable of holding its own in the favela. It also suggests that fully consolidating security in Alemao may require more resources than authorities expected.

It is particularly troubling that the attack took place in Alemao: the massive complex is among Rio’s largest favelas, a longtime stronghold of its biggest gang, the Red Command (Comando Vermelho), and a symbol of the city’s ambitious public security policy initiatives. Sending another surge of BOPE officers into the area, which has already been presented as pacified, may delay the city’s pacification schedule in other communities.

However, the attack against the UPP may also be indicative that local criminals viewed the police unit as a serious threat which had to be confronted, despite the serious consequences this could bring. The attackers no doubt knew their assault would provoke a major backlash, with the deployment of reinforcements to Alemao, yet they felt compelled to attack the UPP unit regardless.

It is also worth noting that in Alemao and neighboring Penha, another large favela, the UPP have 25 percent fewer personnel deployed in the neighborhood than the military had before them, according to news site IG. The police also reportedly carry less powerful equipment, making them more vulnerable than soldiers.