The escalating conflict between the ruling Popular Party (PP) and its former treasurer, Luis Bárcenas, took a new turn on Friday when national police showed up at PP headquarters to investigate Bárcenas’ claim that two computers and personal papers were stolen from the office he allegedly had there.

Several police officers walked into party headquarters on Madrid’s Génova Street with a warrant on Friday to find out from a high-ranking official whether Bárcenas was truly using the office that he claims the material disappeared from, sources at the Madrid police department confirmed. Other sources said that members of the forensic police inspected the room in question, known as Sala Andalucía.

The PP told the police that “Mr Bárcenas does not have an office at PP headquarters.” The former treasurer, however, has directly accused Alberto Durán, a lawyer and top aide to PP secretary general Dolores de Cospedal, of ordering the theft of his computers and documents. The daily La Gaceta reported on Friday that two workmen had forced the lock on the room and cleaned it out.

This is just the latest in a flurry of complaints, lawsuits and counter-lawsuits being filed by all the parties involved in the expanding Bárcenas case. Alberto Durán earlier filed a lawsuit against Bárcenas and EL PAÍS in Cospedal’s name, while the PP is suing the United Left (IU) for libel after the IU brought action against the PP for serious crimes committed by its leaders, in reference to alleged illegal party financing and dubious cash payments to PP officials, all of which was documented by Bárcenas in secret ledgers that were recently published by EL PAÍS.

Earlier this week it emerged that Bárcenas was suing the PP for unfair dismissal. The party maintains that the ex-treasurer stopped working for the PP in 2010 after being implicated in a parallel scandal, the Gürtel kickbacks-for-contracts case. However, Bárcenas insists that he served as an advisor to the party from March 2010 until January 31 of this year. De Cospedal claimed that after Bárcenas stopped working in 2010 he agreed to draw his severance pay on a monthly basis, with monthly Social Security and tax deducted from it.

On top of all this, it recently transpired that Bárcenas was concealing a personal fortune of around 38 million euros in Swiss bank accounts, the origin of which remains murky. Bárcenas claims this money comes from art sales, consulting work and investments in real estate and the stock market.

In an attempt to start joining up the dots, investigating judge Pablo Ruz, who is in charge of the Gürtel bribes-for-contracts case affecting many PP officials (including Bárcenas, who lost his senator’s seat and was allegedly dismissed by the PP in 2010 over the issue), is trying to establish whether the kickbacks paid out by Gürtel coincide in any way with the sums of money showing up on the secret ledgers that Bárcenas allegedly kept, documenting illegal donations from construction tycoons and cash payouts to PP leaders, including current Prime Minister Mariano Rajoy. These ledgers show as much as 7.5 million euros of opaque money coming into the party between 1990 and 2008.

The ruling party is also planning a collective suit against Bárcenas, who has gone from being its trusted aide to the bane of the PP’s life.