Former Petrosaudi International executive Xavier Justo has described the arrest of former premier Najib Abdul Razak as “just the beginning”.

"It's a day to celebrate, but we have to keep in mind that it's just the beginning. Other accomplices have to be arrested in Malaysia and other parts of the world,” he told The Star.

According to the report, Justo was “overjoyed” to hear of Najib's arrest.

"Today, we are Malaysians.

"I have suffered so much with my wife in exposing this Malaysian scandal, that part of us is bonded forever with Malaysia," he said.

Justo, who implicated PetroSaudi owner Tarek Obaid and its chief investment officer Patrick Mahony in the 1MDB scandal, said the saga would only be over for him when all the culprits are behind bars.

"It's not the end, but an extraordinary day to celebrate," he added.

Previously, Justo had pledged to continue to help Malaysia in any way possible, including testifying in trials here.

MACC had arrested Najib at his residence in Jalan Duta this afternoon over the commission's investigation into SRC International.

Following this, the 1MDB taskforce said the former premier is expected to be charged at the Kuala Lumpur Sessions Court tomorrow morning.