A Basque separatist group attacked a Spanish airport with home-made mortars Friday, forcing holidaymakers to flee and apparently signalling the start of a campaign against tourist targets.
At least two mortars were fired at the airport in Zaragoza, 240km east of Madrid, though there were no injuries and it was unclear last night exactly where they had exploded.
Police confirmed that two home-made mortar launchers had been found in undergrowth near the airport and a search was continuing last night to see if there were any more.
A Ryanair flight from London Stansted was diverted to a nearby military airport after the separatist group ETA issued a warning saying that there would be an attack on the city's civilian airport.
A Ryanair spokeswoman said: "The aircraft parked at a military [base] and all passengers disembarked. The passengers and aircraft remained [there] until the security alert at the airport had ended ... Passengers were then coached to the terminal building."
Passengers on the return flight "waited in a safe zone outside the airport," she said. The flight eventually left more than two hours late.
Television pictures showed the passengers walking down a road away from the airport and seeking shade under nearby trees.
A short while later witnesses said two mortar shells could be heard whistling through the air towards the airport.
The attack appeared to confirm police worries that ETA would carry out attacks on tourism targets this summer, despite rumors that it may be about to enter into peace talks with the Spanish government.
The Vanguardia newspaper reported last week that anti-terrorist police had increased their watch on the frontiers with France, fearing that ETA units hiding there were likely to start a campaign targeting tourist sites.
The telephoned warnings, which gave police less than an hour to evacuate the airport, indicated that ETA may, however, be taking measures to avoid killing anyone while the promise of talks hangs in the air.
ETA has killed more than 800 people during the three decades of violence since it took up arms.
But a much weakened ETA has not managed to kill anyone for more than two years amid a sustained police crackdown which has taken the number of its members in jail up to 700.
The Socialist prime minister, Jose Luis Rodriguez Zapatero, said earlier this week that 178 ETA suspects had been jailed since he took office 14 months ago. Zapatero repeated earlier this week that he was prepared to talk to ETA if the conditions were right.
"If the government finds proof that there is a chance ETA is willing to abandon arms and stop using violence forever, of course the government will talk to search for peace," he said.
However, a quarter of a million marchers took to the streets of Madrid last weekend to demand that there be no negotiating with terrorists.
Some observers said yesterday's attack was proof that ETA would never give up violence.
"What ETA is trying to say is that it does not want talks with anybody and will continue with its strategy of terror," said the socialist mayor of Zaragoza, Juan Alberto Belloch.
ETA has carried out attacks against tourism targets most summers for the past two decades.