Iraqi warplanes bombed Iranian cities Monday, reportedly killing at least 17 civilians, and both sides claimed victory in a furious weeklong battle for strategically important marshland along the southern frontier.
In Baghdad, the Iraqi capital, witnesses reported a powerful explosion near the residence of President Saddam Hussein.
The Iranian news agency IRNA said Iran had fired a long-range, non-nuclear missile into Baghdad at midday. It urged people to leave the city so other Iranian missiles would "only hit the Iraqi criminals and their palaces."
Iraqi officials did not comment on the explosion, but they have blamed two previous blasts in the capital on bombs placed by saboteurs.
The latest fighting in the 4 1/2-year-old Persian Gulf War came a day before an Iraqi blockade of commercial airline flights into Iran was to go into effect.A number of airlines, including British Airways and West Germany's Lufthansa, have canceled service to the Iranian capital. Some also canceled flights to Baghdad.