Investigations into the Popular Party's ex-treasurer Luis Barcenas have rattled Prime Minister Mariano Rajoy's government as it tries to steer Spain out of a deep recession, having narrowly avoided seeking a sovereign bailout last year.
As Barcenas went before a judge for questioning today, sources at the court said state prosecutors had asked for him to be held in custody.
Rajoy and the party have distanced themselves from Barcenas but his detention would be a dramatic development in a saga that has tainted the highest ranks of the PP.
In one, Barcenas is accused of channelling undeclared payments to top party members.
More From This Section
The judge was questioning him today in a separate strand of the probe, concerning tens of millions of euros he allegedly held in Swiss accounts.
Prosecutors demanded unconditional detention on the grounds that Barcenas was a flight risk, said a court source who asked not to be named.
"The risk of flight has increased because Switzerland says he has been raising funds in the United States and Uruguay from those of his Swiss accounts that have not been blocked," the source said.
Leading centre-left newspaper El Pais in January published extracts of account ledgers that appeared to show tens of thousands of euros from donors being channelled to senior Popular Party officials, including Rajoy.
Rajoy has denied receiving undisclosed payments and both he and Barcenas say the ledgers are false.
In February the prime minister rejected calls to resign over the scandal, which has fanned outrage among Spaniards enduring the spending cuts he has imposed in the recession.