SAO PAULO (Reuters) - More than 50 police officers who patrolled the same area in Sao Paulo were arrested on Tuesday, accused by state prosecutors of taking bribes from Brazil’s largest drug gang to allow its members to sell narcotics, authorities said.

The Sao Paulo state police’s internal investigations unit worked with state prosecutors who focus on combating the powerful First Capital Command (PCC) drug gang to gather what prosecutors said in a statement was proof of collaboration between officers and the cartel.

The PCC has rapidly grown in strength in recent years, investigators say, now largely controlling cocaine and gun shipments into Brazil and also the flow of drugs grown in neighboring countries and shipped to Africa and Europe through Brazilian ports.

By late afternoon, 53 members of the 22nd Battalion of the Sao Paulo state police were under arrest - nearly 10 percent of that battalion’s entire force, according to state prosecutors. Three suspected PCC members are also in custody.

Battling Brazil’s rampant crime and ever-growing drug gangs is a top priority for President-elect Jair Bolsonaro, who campaigned on a law-and-order platform and openly calls for police to assassinate suspected drug gang members.

Tuesday’s operation in one of Brazil’s safest states, however, underscored the complexity of the country’s security situation, with poorly paid and trained police routinely being found to tip off drug gangs about police raids, or being active members of paramilitary militias that battle the drug gangs for turf.