Spanish police carried out a more than 14-hour search of the Popular Party’s (PP) main headquarters in Madrid that concluded Friday morning as part of the High Court’s ongoing corruption investigation into the ruling party’s finances.

The search was ordered by High Court Judge Pablo Ruz who issued a 15-page writ identifying a dozen reasons why he believed that the PP wasn’t cooperating fully with the investigation into under-the-table money that may have ended up in the party’s coffers.

Ruz is in charge of two ongoing investigations: the massive Gürtel kickback-for-contracts inquiry that has ensnared various local and regional PP administrations and the probe into secret accounting ledgers kept by now-jailed former PP treasurer Luis Bárcenas.

In Brussels, Prime Minister Mariano Rajoy told a news conference that he had ordered his party officials to cooperate in the inquiry. “I have absolute respect for any decision made by the courts,” Rajoy said. “We're waiting for their decision, but we're not worried.”

Specifically, Ruz ordered the police to confiscate documents related to the remodeling of the PP headquarters on Génova street. The judge believes that 5.6 million euros paid to architect Gonzalo Urquijo were undeclared and may have come from a slush fund maintained by Bárcenas. Urquijo has been named as a target in the inquiry.

Last month, the party's secretary general, María Dolores de Cospedal, said that all the payments made to Urquijo were on the party’s official books.

But in his writ issued on Thursday Ruz said Bárcenas, along with his predecessor Álvaro Lapuerta and former party official Cristóbal Páez, conspired with Urquijo to come up with false documents and bills to make it look like the architect was paid a certain amount. Ruz said that emails between employees at Urquijo’s Unifica firm and between the architect and Paéz support this allegation.

He ordered officers from the UDEF economic crimes task force to confiscate all records and computer files at party headquarters related to Bárcenas, Lapuerta and Paéz, as well as the PP’s accounting records. The three men are all official targets in the ongoing inquiry.