Brazilian police announced a huge drug trafficking bust on Thursday that saw at least 26 people arrested and several aircraft seized in an operation targeting a narcotics network that had transported nine tons of cocaine between 2017 and 2018.

Federal police said in a statement that 400 officers were involved in the operation in the northern state of Tocantins.

Authorities there are also attempting to block the accounts of "around 100 implicated people and businesses," and seize "47 aircraft and 13 ranches with more than 10,000 head of cattle," the police statement said.

The police didn't say how many planes had been seized but sent a video to AFP that showed at least seven in a hanger.

The drugs were transported by plane from Bolivia, Colombia or Venezuela to Brazil, Europe and the United States.

A police source told AFP that some of the seized ranches were equipped with landing strips while others had been bought through the proceeds of drug trafficking.

Authorities have also requested that six suspects be placed on Interpol's wanted list.

The investigation, which began two years ago, detected "at least 23 flights that carried on average 400 kilograms of cocaine each, making a total of more than nine tons."

The US Drug Enforcement Administration (DEA) and Surinam's anti-terrorism agency (CTIU) were also involved in the investigation, the police said.

That led to the seizure last year in Surinam of a submersible vessel capable of carrying eight tons of drugs as far away as the African coast.

Last week, jailed leaders of the PCC, one of Brazil's main criminal gangs, were transferred to a maximum-security facility.

That "isolation" is aimed at "dismantling criminal organisations," Sao Paulo governor Joao Doria said.

In early December, a huge anti-drug operation was carried out in 14 states with 262 arrest warrants issued and 200 seizures.