Finger-pointing in the German parliament over Wirecard AG's disintegration now has in its crosshairs authorities who allegedly failed to scrutinize the payments group before it became the nation's biggest fraud.

German politicians Tuesday opened an in-depth legislative investigation into Wirecard in an attempt to squeeze more information from the government about negligence and to stave off a high-profile accounting mess.

Opposition politicians on the left including members of the liberal Free Democrats said they had formed a committee to press the ruling coalition - including the Social Democratic Party and Christian Democratic Union - to launch a full investigation.

The investigation will dig into what the government knew and whether the country's financial watchdog had been remiss about issues and concerns about the credit card company's nature of business.

According to Greens legislator Lisa Paus, parliamentarians have been forced to believe that the government is refusing to communicate or cooperate. No one from the government is "willing to take responsibility," she said, following a two-day hearing at the German federal parliament.

Politicians questioned a senior adviser to German Chancellor Angela Merkel and will grill finance industry regulators Wednesday. The scandal exposed a huge crack in the government's financial oversight and put the nation's political integrity in a bad light.

Analysts say the inquiry into the implosion of a company once touted as a German success story will put more burden on Merkel and her deputy Olaf Scholz in the run-up to the 2021 national polls.

Considered to be the "darling" of the German financial scene, Wirecard was exposed in June to have "lost" $2.27 billion from its balance sheets.

The company's auditor Ernst & Young, who refused to sign off on Wirecard's accounts because of the alleged missing funds, said there were clear signs the payments group carried out a "sophisticated fraud" involving many around the world.