MADRID (AP) — The president of the Madrid branch of Spain's center-right Popular Party resigned Sunday amid allegations that the party benefited from irregular funding.

Esperanza Aguirre, 64, who had been president of the Senate and then Madrid's regional president until 2012, said she was shocked by revelations her party could have been involved in corruption.

At a hastily-convened news conference, she said that as the party's Madrid president she has "no culpability, but a political responsibility that I assume by resigning."

On Friday, Aguirre appeared before the Madrid Assembly as it held a commission of inquiry into political corruption. A day earlier, police searched the Popular Party's national headquarters in Madrid on orders given by a National Court judge who is investigating illegal financing.

"The news about corruption is killing us," Aguirre said. "The people want action. That's why I'm resigning."

Judge Eloy Velasco ordered that the offices of Beltran Gutierrez, who had worked under Aguirre in the party, should be searched.

The Popular Party has been in power with Mariano Rajoy as prime minister since 2011, but although it was Spain's most voted party in the Dec. 20 general election, it fell short of obtaining a parliamentary majority.

As no party won a majority in the 350-seat parliament, Rajoy currently leads a caretaker government while negotiations take place to see if a coalition can be formed to rule Spain.