Bomb blasts at Istanbul's airport and a railway station killed three persons and one man was wounded in a gunfire attack on opposition leader Bulent Ecevit today as Turkey's violent election campaign entered its final week.

Thirty persons, including an unidentified American woman, were wounded in the blast at Istanbul's international air terminal.

Nine were hurt when an explosion went off in Istanbul's west railway station. Police said the air terminal and railway station explosions were caused by bombs planted in luggage storage rooms.

The two explosions coincided with a rally organized by the National Salvation Party, which advocates a return to Islamic fundamentals.

A bullet fired at Ecevit hit one of the ex-premier's supporters as he and a campaign party arrived at Izmir airport. It was the fifth attempt on Ecevit's life in three weeks.

The day's violence brought the death toll in campaigning for Turkey's national elections June 5 to more than 10.

Besides being the most violent, it is also the most colorful and intensely fought of Turkish election campaigns.

Ecevit, leader of the liberal Republican People's Party campaigns from the top of a red-striped bus and promises social justice.

Prime Minister Suleyman Demirel, head of the conservative Justice Party, campaigns from replicas of his government's achievements, such as the Bosporus Bridge, and promises to crush communism.

Not to be outdone, Necmettin Erbakan, leader of the National Salvation Party, promises to restore Turkey to its former imperial glory with in 25 years, and plans to campaign from a 30-foot-high copy of an Ottoman palace.

While the campaign is full of such gimmickry, behind the rhetoric there are serious problems.

Turkey can no longer pay its import bills and faces an almost - certain devaluation of the lira, the third in 12 months. Inflation is running at 18 per cent annually, and 2.5 million Turks are unemployed.

Turkey is becoming increasingly isolated from its Western allies over Cyprus, is rejected by the Third World because of its ties with NATO, and is being wooed by its former worst enemy, The Soviet Union, whose intentions the Turks feel may not all be honorable.

Street and campus violence occur's almost daily and nearly 200 persons have died and 4,000 have been wounded in political clashes in the past two years.

It was in an effort to end the deaths that the main contenders, Ecevit and Demirel, agreed in a rare show of unity to bring the October elections forward three months, to June. Nevertheless, 34 persons were killed at a May Day rally and violence has dogged the campaign.

Ecevit has been shot at four times. The 51-year-old poet-politican became a national hero during his short premiership in 1974 by ordering the invasion of Cyprus to block an Athensbacked attempt to unite the island with Greece.

Demirel, 52, was the target of stones while campaigning in western Turkey. A bomb exploded in Mersin's main square shortly before Alpaslan Turkes, leader of the neo-Facist National Action Party, was scheduled to address a rally. There were no injuries.

Both right and left have accused each other of fomenting the violence since Demirel came to power in March, 1975, following the collapse of the Ecevit government.

But a report issued by Amnesty International in April put the blame for the disturbances on the rightists and said te Demirel government and police had made no real attempt to curb the killings.

Campaigning officially ends at dusk June 4. Voting the next day will be under strict security, but disturbances are expected. And when the votes are counted, the outcome is likely to be inconclusive.

A shift from right to left is expected because of the division of the rightist vote between Demirel and Erbakan and swelling of the leftist vote by 4 million first-time voters.

But Ecvit's Republicans, who energed as the largest party in the 1973 election with 185 seats, are unlikely to win an absolute majority in the 450-seat assembly.

Demirel's Justice Party, which won 149 seats in 1973, is expected to retain second place in Parliament, and Erbakan's National Salvation Party third.

The policies of the new government would then depend on which of the party leaders is successful in piecing together a coalition.

Neither Ecevitn or Demirel is likely to have enough support to feel confident enough to make concessions on Cyprus, a necessary first step to improving relations with the United States.