As rioters battled police in clashes that left two people wounded Friday, European Union leaders struggled to keep their plans for expansion on track despite Irish opposition.

Hundreds of youths espousing support for a variety of anti-capitalist causes hurled cobblestones at the ranks of riot-squad officers and attacked banks, stores and cafes around Goteborg's elegant downtown in the kind of violence that has become a familiar feature of international meetings.

Two shooting victims were hospitalized after clashes in a park outside the complex where the EU leaders were, according to hospital spokeswoman Annika Hedelin. She couldn't give further details, but the Swedish news agency TT cited a policeman saying at least one person had been shot as anti-EU protesters battled riot police.

Police could not be reached for immediate confirmation.

The riot, which lasted over an hour, and other clashes were sparked by a small minority of the estimated 25,000 protesters who converged on the Swedish port city for the summit. A hospital official said 27 demonstrators and 10 police officers were hurt, but the injuries were not life threatening.

The mayhem forced the EU leaders to change their dinner plans from a posh parkland restaurant to the conference center, where the summit was held behind police barricades. They condemned the rioters for attacking elected governments and undermining the rights of peaceful protesters.

"We have to pursue these rioters with all the might of the law," German Chancellor Gerhard Schroeder said at a news conference. "No country should tolerate these criminals."

Closeted in the conference center, the EU leaders reassured rattled eastern neighbors that a referendum last week in Ireland had not shut the door on their hopes of joining the trading bloc.

On June 7, the Irish voted 54 percent to 46 percent to reject the Treaty of Nice, a complex document to overhaul the EU's rule book and open the door for a dozen new members, most of them former Soviet republics or satellite states.

"The 'no' vote should not be interpreted as a vote against enlargement," Irish Prime Minister Bertie Ahern insisted. "I do not see any reason why any of this should change the timetable."

The Nice treaty was adopted last December after months of tough negotiations, but must be ratified by all 15 EU members. Ireland is the only one that allows its citizens to decide directly.

Since barely a third of voters turned out for the referendum, officials are confident the result can be turned around. Ahern said he would launch a "national period of reflection" on the issue, but set no date for a new vote.

In the face of the setback, the EU's commitment to press ahead in nearly doubling its membership received the backing of President Bush, on a European tour that took him Friday from Goteborg to Poland – one of the front-runners for EU membership.

"I believe we have an opportunity to form an alliance of peace, that Europe ought to include nations beyond the current scope of the European Union and NATO," Bush told EU leaders Thursday. "I strongly believe in NATO expansion, and I believe the EU ought to expand as well."

The EU already has a tentative timetable to wrap up negotiations with leading candidates by the end of 2002, launching a ratification process that could mean membership for the first new entrants by early 2004.

However, leaders of the applicant nations – who were to attend the summit's final session Saturday – hoped for a firmer pledge.

Poland, Hungary, Slovenia, the Czech Republic, Estonia, Malta, Slovakia, Cyprus, Latvia, Lithuania, Bulgaria and Romania are all negotiating for membership. Turkey also has applied, but has not yet started membership talks.