Eight suspected Islamic militants have been arrested in raids across Spain.
Spanish police launched raids across the country
Interior minister Jose Antonio Alonso said police had broken up a radical Islamic cell believed to be plotting to blow up the High Court in Madrid.
Seven men were arrested on Monday while another suspect was detained in the northern city of Pamplona on Tuesday.
It is seven months since Islamic militants launched bomb attacks on trains as they arrived in Madrid, killing 191 people.
Around 20 suspects are being held in custody because of alleged links to the attacks.
A further seven were killed when their explosives blew up as police approached their hide-out in Madrid.
No weapons or explosives were seized in the raids on Monday and Tuesday, but officials said there was believed to have been a plan to detonate a lorry packed with explosives.
"They were talking about an attack on the High Court or another judicial body but police are not ruling out other possible targets," Interior Minister Jose Antonio Alonso told reporters.
The High Court handles cases of terrorism and is where the suspected Madrid train bombers are under investigation.
Of the seven people arrested on Monday, four were arrested in the southern city of Almeria and the other three in the southern town of Malaga, the eastern city of Valencia and Madrid.
The suspects were said to include at least four Algerians and one
The interior ministry said the suspects had been in contact with other individuals in Europe, the US and Australia.