MEXICO CITY - Mexico is investigating suspected corruption linked to the $32 million purchase of Pegasus malware allegedly used by authorities to spy on political opponents and journalists, a government agency said Wednesday.

An international media investigation revealed this week that 15,000 Mexican smartphone numbers were among more than 50,000 believed to have been selected by clients of Israeli firm NSO, which developed Pegasus.

They include numbers linked to 25 journalists and even leftist President Andres Manuel Lopez Obrador's inner circle before he took office.

The graft probe is focused on two Mexico-based companies, Balam Seguridad Privada and Grupo Tech Bull, the director of the Financial Intelligence Unit, Santiago Nieto, told reporters.

Grupo Tech Bull obtained a contract with the attorney general's office for the purchase of Pegasus spyware for $32 million in 2014 when Enrique Pena Nieto from the Institutional Revolutionary Party (PRI) was president, he said.

Another firm linked to Grupo Tech Bull called KBH was in charge of transferring the money to NSO.

The funds ended up in Italy, the United States and Israel, Nieto said, adding that Grupo Tech Bull was suspected of being a front company.

Mexican authorities are investigating possible money laundering and tax evasion and will block the accounts of 24 people linked to the case, he added.

According to the Pegasus Project investigation, Mexican agencies that have acquired the spyware also include the defense ministry and the national security intelligence service.

Lopez Obrador has said that the authorities now only spy on criminals and not political opponents or reporters.

Allegations that Pegasus was used to target more than a dozen heads of state and hundreds of journalists have prompted demands for Israel to suspend exports of spying technology.