Spanish prime minister Mariano Rajoy and his government have been rocked today by documents published in El Pais that appear to show his party receiving a large amount of "secret" donations.

El Pais claims that the documents show a series of payments from well known businessmen to the conservative People’s Party for more than a decade, with the last payment in 2009.

According to the Guardian, one document appears to show Rajoy himself receiving payments totaling €250,000 ($340,000) that had been hidden from tax authorities.

The scandal revolves around former treasurer Luis Bárcenas, who is under investigation for allegedly having €22 million ($30 million) in a Swiss bank account. Bárcenas is alleged to have kept a double accounting system for the party to hide the payments.

For the Spanish government this timing is bad — CNN notes that just one day ago there was a parliamentary debate over how to stop corruption. The country is currently suffering from one of the worst unemployment rates in Europe, and has seen widespread protests on the streets of its major cities.

Two senior PP party members have admitted that at least some of the payments are true, but the party itself is denying the report, the Guardian reports.

"The party vehemently denies the contents of these documents," party secretary general Maria Dolores de Cospedal said, adding that they may sue El Pais. "I have spoken to the prime minister and he is calm."