BERLIN, May 18 (Xinhua) -- The German Federal Office for Migration and Asylum (Bamf) is reviewing around 18,000 successful asylum applications in response to serious irregularities at its Bremen branch, the organization's director Jutta Cordt told the press on Friday.

Speaking in Berlin, Cordt explained that the comprehensive assessment would take three months in total and involve 70 Bamf employees. The objective of the investigation was to review every case in which asylum status had been granted to refugees by the Bremen office since the year 2000.

"We are in the process of clarifying the matter and this effort is still ongoing," the Bamf director said.

A senior Bamf employee in Bremen stands accused of incorrectly granting humanitarian residency in Germany in thousands of applications asylum seekers between 2013 and 2017. The Bremen State Prosecution Office confirmed that it was investigating the Bamf employee in question, as well as three attorneys and one translator who are believed to have cooperated systematically in subverting the course of justice.

The suspects face criminal charges of corruption and organized incitement of filing fraudulent asylum applications. A spokesperson for the interior ministry subsequently emphasized that the accusations only concerned an "isolated case."

According to Cordt, so far, around 600 reviewed cases handled by the suspected lawyers were found to have severe procedural flaws. Where necessary steps would be taken to revoke incorrect asylum decisions, although this would involve a lengthy and complicated judicial process.

In an address to parliamentary delegates, interior minister and Christian Social Union (CSU) leader Horst Seehofer said that he remained convinced that the Nuremberg-based Bamf did its job well as a whole and consequently did not deserve to be placed under collective suspicion. However, the minister has also come under heavy attack himself in the affair for allegedly withholding information from the public.

Josefa Schmid, a civil servant who was posted to the Bamf Bremen office as an interim director following the first revelations of the scandal, told the press that she personally informed the minster in March about 3,332 asylum decisions which she believed to be incorrect. By contrast, Seehofer insists that he was not made aware of the findings by Schmid until April.

Earlier reports put the total number of potentially manipulated cases lower at between 1,200 and 2,000 in total. In the meanwhile, Schmid has been reordered from the Bremen Bamf office back to her home state of Bavaria, a decision which she is attempting to appeal.