Portuguese police have seized half a tonne of explosives at a house being used as a base by Basque separatist group Eta. The discovery, which also included bomb-making equipment, was made in the central Portugal town of Obidos. Officials said fake licence plates, detonators and maps were also found. Local police chief Helder Barros said several of the explosives were ready to be used. A militant group fighting for an independent Basque homeland, Eta has been blamed for more than 820 deaths during its campaign in Spain. Reports say the discovery appears to confirm what many have suspected for some time – that Eta is using sites in Portugal to prepare attacks in Spain.