'I wished I was on that plane': Iranian general apologizes; missiles pound Iraq base. What we know now

John Bacon | USA TODAY

Show Caption Hide Caption Protests erupt after Tehran admits Ukrainian plane crash unintentional President Donald Trump tweeted his support for anti-government protests after Iran admits they accidentally shot down the passenger jet.

Fallout from Iran-U.S. tensions intensified Sunday as missiles pounded an Iraqi air base hosting U.S. troops while Iranians defied a government crackdown and protested their government's accidental shootdown of a passenger jet.

Gen. Hossein Salami, head of Iran's Revolutionary Guard, apologized for the jet tragedy. And President Donald Trump tweeted his support for the demonstrations, warning there "cannot be another massacre of peaceful protesters."

Iran-U.S. relations have been devolving since Trump pulled the U.S. out of a global pact with Iran, fashioned by the Obama administration, that eased some economic sanctions in return for Iran curbing nuclear development.

Tensions reached new highs after a U.S. drone strike Jan. 3 that killed Iranian Gen. Qasem Soleimani. Soleimani's death drew millions of angry, mourning Iranians to the streets of Tehran and other cities. It also drew retaliation.

Here is what we know so far:

4 hurt as missiles slam air base

Four Iraqi soldiers were wounded Sunday when at least six rockets slammed into the Balad air base 50 miles north of Baghdad, the Iraqi military said. There was no immediate word of U.S. casualties, and officials said most U.S. troops had left the area in recent days. The statement made no mention of Iran, and no group or nation immediately took responsibility for the attack.

U.S. death heightened tensions

The attack on Soleimani came days after a U.S. contractor was killed in a rocket attack at an Iraqi air base. U.S. officials blamed the attack on Iranian-backed militias, and the U.S. response was a drone strike on Soleimani, who was in Iraq at the time. The strike drew outrage from Iran and Iraq. In Iraq, lawmakers voted to order U.S. troops to leave the country. In Iran, authorities promised a military response.

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Iran's military response not bloody

Iran responded early Wednesday by firing missiles at two bases in Iraq housing some U.S. troops. Iran provided Iraq with some notice, and U.S. missile defenses saw the missiles coming. The result: No deaths or injuries were reported. Iran also announced that it would abandon the remnants of the 2015 nuclear deal but said it had concluded its retaliation for Soleimani's death. Trump said the U.S. would respond with tighter economic sanctions but issued no military warning.

Iran makes deadly mistake

Hours after the missile strikes, a Ukrainian commercial jet with 176 people aboard crashed shortly after takeoff from Tehran. Iranian officials at first rejected claims the plane was shot down but later acknowledged responsibility. Iran said the plane turned toward a military installation, already on high alert, and was mistaken for a "hostile target" and shot down.

Salami: 'I wished I was on that plane'

The Iranian military promised to deal with the plane strike in military court. “I swear to almighty God that I wished I was on that plane and had crashed with them and burned but had not witnessed this tragic incident,” Salami said Sunday. “I have never been this embarrassed in my entire life. Never.”

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Iranians protest tragedy

Protesters have taken to the streets in Iran, shouting slogans and demanding that leaders be held accountable. Hadi Ghaemi, the executive director of the New York-based Center for Human Rights in Iran, tweeted: "The brave people of Iran have a right to peacefully mourn and demand accountability from their government without state violence, and that government has a duty to listen." Iranian President Hassan Rouhani issued a statement assuring that those who are responsible for the tragedy will be prosecuted.

Protests not new in Iran

Iran had been rife with protests before the latest clash with the United States. Economic difficulties, in part because of crushing global sanctions had led to a 50% fuel price hike in November. That drove thousands of Iranians to the streets in protest and prompted clashes with security forces. Violence, some deaths and sweeping arrests followed, and the government even shut down the country's Internet in an effort to quash the unrest.

Contributing: The Associated Press