Spanish police evacuated the De Lasarte horse racing track in the city of San Sebastian in the country's Basque region after receiving a bomb threat from Eta.
Tension is high in the northern region after the Basque separatist group called off a cease-fire in June which had been in place since March 2006.
On Monday French anti-terrorist police arrested three suspected Eta members as they prepared to cross into Spain in a van packed with explosives.
