Hackers attempted to steal more than 420 million reais (US$77.4 million) from Brazilian banks on Friday by breaching systems operated by financial technology provider Sinqia, a subsidiary of Evertec. The attack targeted Pix, Brazil’s instant payment platform, and was blocked in large part by regulators, according to local media reports.

O Globo reported that roughly 380 million reais were directed at HSBC Holdings Plc’s Brazilian operations, while about 40 million reais were aimed at fintech firm Artta. The Brazilian central bank intervened and stopped about 350 million reais before the transfers were processed. Authorities have not disclosed the status of the remaining funds.

Sinqia confirmed the incident and said the breach was contained to Pix, adding that there is no evidence of unusual activity across its other platforms. The company said Pix has been taken offline while its systems are rebuilt with stronger security controls and will only return after a review by the central bank. No personal data was exposed, according to Sinqia.