Portugal's main opposition candidate in this weekend's European parliamentary elections has collapsed and died after a campaign appearance.
Mr Sousa Franco topped the Socialists' list of candidates
Antonio Sousa Franco, a former finance minister for the Socialist Party, suffered a heart attack after visiting a market in a suburb of Porto.
Campaigning in Portugal has been suspended as a mark of respect.
The elections are taking place across Europe between Thursday and Sunday, with Portugal's vote on Sunday.
Mr Sousa Franco, 61, was finance minister in Portugal's most recent Socialist government from 1995 to 1999.
He imposed tight controls on public spending which made it possible for Portugal to adopt the European single currency as a founder member in 1999.
Thursday: The Netherlands, UK
Friday & Saturday: Czech Rep
Saturday: Latvia and Malta
Saturday & Sunday: Italy
Sunday: Austria, Belgium, Cyprus, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Lithuania, Luxembourg, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden
He suffered a heart attack shortly after campaigning at a fish market in Matosinhos, where a dispute broke out involving supporters of rival factions.
He was unhurt in the altercation and appeared to be well when he left the market.
However, he collapsed shortly afterwards, local deputy mayor Manuel Seabra told Portuguese state radio.
Recent opinion polls have put the Socialists slightly ahead of the governing coalition, which is composed of the Social Democratic and Popular parties.
Portugal is electing 24 members of the 732-seat European Parliament.
It is the first election since the EU expanded to 25 member states on 1 May.
Polling starts in the Netherlands and the United Kingdom on Thursday. Ireland votes on Friday, Latvia and Malta vote on Saturday, and the other countries vote on Sunday.
OUTGOING PARLIAMENT: BREAKDOWN OF SEATS
EPP-ED: European People's Party-European Democrats (Centre-Right)
PES: Party of European Socialists (Socialists)
ELDR: European Liberal, Democrat and Reform Party (Liberals)
EUL/NGL: European United Left / Nordic Green Left (Far Left)
Greens/EFA: Greens / European Free Alliance (Greens and regionalists / nationalists)
IND: Independents, not attached to any group
UEN: Union for Europe of the Nations (Right wing / Gaullists)
EDD: Europe of Democracies and Diversities (Eurosceptics)
The Czech Republic has two days of voting on the Friday and the Saturday, and Italy votes on Saturday and Sunday. No results will be announced until after the last polling station closes on Sunday.
Around 350 million Europeans are eligible to vote in the elections, but turnout is expected to be less than 50%.
The BBC's Caroline Wyatt, in France, says apathy on Europe is rife.
She says France's governing centre-right fears that voters could use this as a chance to vote against the government on domestic rather than on European issues.
Analysts are suggesting recent world events are also going to have an impact on the elections.
It is hoped that the show of unity over an Iraq resolution at the United Nations on Tuesday will encourage voters.
In Italy, the return of three Italians taken hostage in Iraq is being seen as a boost to Prime Minister Silvio Berlusconi, who considers the polls a test for his government.
A majority of Italians have been against Mr Berlusconi's support for the US-led war in Iraq.
But some Italian papers say the hostages' rescue and the passing of a UN-resolution on Iraq have given Mr Berlusconi reason to "gush satisfaction".
In the UK, a pilot postal voting scheme appears to be helping turnout.