Citing the government's annual corruption prevention study for 2015, "Welt am Sonntag" (WamS) has reported that Germany's most frequent allegations of formal graft relate to the issuing of visas by the Foreign Ministry.

The ministry has already taken disciplinary action in 11 cases involving 15 accused officials, WamS reports. Ten cases involved questionable visas.

In the other case, two employees allegedly received 10,000 euros from a construction firm seeking building contracts.

One of the accused civil servants was hit with a 50 percent salary cut, WamS reports.

Rise in case investigations

Compiled by Germany's Interior Ministry, the study suggests an increase in reported cases of corruption. For comparison, there were 19 such corruption probes in 2014 and 12 in 2013.

The biggest losses due to corruption occurred in Germany's federal Environment, Nature Conservation, Building and Nuclear Safety Ministry. An employee allegedly disclosed important information to a firm, giving it an advantage during the bidding process for a contract. The same employee then signed falsified invoices, according to WamS. Losses came to about 870,000 euros.

In another case, a Bundeswehr employee was dismissed for receiving an iPad, a laptop and money.

Left unnamed by WamS, the firm that had tried to curry the military employee's favor with high-tech gifts was especially brazen: The cost of the backhanders was included in an invoice sent to the Bundeswehr.

Two customs officers were suspected of granting favors in exchange for tickets to a concert.

Another customs officer was suspected of helping a firm in southeast Asia to evade tax, according to WamS.

One officer ended up last year with a jail term of four years and 10 months for being an accomplice to tax evasion, breach of trust and corruption.

And there were three cases of suspected corruption in the Labor Ministry.

In one case a training course participant filed charges against several recruitment center officials after they allegedly took money for allocating jobless people to courses.

WamS noted that Transparency International(TI) continues to rank Germany relatively high in comparisons across the European Union.

Germany lays on par with Britain and Luxembourg, at fifth place on TI's scale based on levels of honesty and corruption internationally.

EU civil servants in Hungary, Slovakia, Greece, Romania, Italy and Bulgaria are more susceptible to corruption, according to TI.