Freshman Democratic Rep. Ilhan Omar clashed with President Donald Trump's envoy to Venezuela in a congressional hearing Wednesday, blasting what she suggested was his indefensible human rights record and demanding to know why lawmakers should consider him a credible witness.

Elliott Abrams, Trump's envoy, was an assistant secretary of state under President Ronald Reagan. He was convicted in 1991 of withholding information from Congress during the Iran-Contra scandal, in which U.S. officials secretly facilitated the sale of arms to Iran and funneled the money to rebels fighting Nicaragua's leftist government.

President George H.W. Bush pardoned him in 1992. Omar used his past in her line of attack, although she mispronounced 'Contra' as she read from her notes.

'I fail to understand why members of this committee or the American people should find any testimony that you give today to be truthful,' she told him.

Elliott Abrams is President Trump's envoy to Venezuela, a country whose socialist government is teetering on the brink of collapse; he testified in a tense House Foreign Affairs Committee hearing on Wednesday

Freshman Democratic Rep. Ilhan Omar said Abrams shouldn't be considered a credible witness because he lied to Congress in the 1980s about the Iran-Contra affair: 'I fail to understand why members of this committee or the American people should find any testimony that you give today to be truthful'

Abrams, 71, asked if he could respond, but Omar told him it wasn't a question.

'It was an attack,' he snapped back. 'It wasn't right.'

'It's not right that a member of the committee can attack a witness, who is not permitted to reply!' Abrams added.

'That was not a question,' the 37-year-old scolded. 'Thank you for your participation.'

Omar, a Muslim lawmaker allied with Democratic socialist alexandria Ocasio-Cortez, complained about U.S. support for anti-communists in Central America during the Cold War.

She cited Abrams' initial dismissal of reports of the 1981 El Mozote village massacre in El Salvador as left-wing propaganda.

The Salvadoran Army infamously slaughtered more than 800 civilians on a December day that year, carnage for which it apologized 30 years later.

'Would you support an armed faction within Venezuela that engages in war crimes, crimes against humanity or genocide if you believe they serve the U.S. interests as you did in Guatemala, El Salvador or Nicaragua?' Omar asked Abrams.

'I am not going to respond to that question,' he replied, calling it an undeserved personal attack.

'It's not right that a member of the committee can attack a witness, who is not permitted to reply!' Abrams, 71, complained. 'That was not a question,' the 37-year-old scolded. 'Thank you for your participation'

Abrams insisted that U.S. involvement in El Salvador was a success since the country has resisted communist insurgencies, despite elections that some observers considered fraudulent.

'From the day that President [José Napoleón] Duarte was elected in a free election, to this day, El Salvador has been a democracy. that's a fabulous achievement!' he said.

'Do you think that massacre was a fabulous achievement that happened under our watch?' Omar retorted.

'That is a ridiculous question and I will not respond to it,' he said.

'Yes or no?' she pressed.

'No!' Abrams erupted.

'I'll take that as a "yes",' Omar snarked.

Abrams directed his next comments to the Democratic chairman of the House Foreign Affairs Committee, Eliot Engel.

'I'm sorry, Mr. Chairman, but I am not going to respond to that kind of personal attack which is not a question,' he said.

Abrams drew intermittent outbursts from protesters during Wednesday's hearing.

Venezuelan strongman Nicolás Maduro, pictured Sunday at the launch of new military drills, is facing a battle to maintain power in the country after opposition leader Juan Guaido was recognised by some 50 countries as interim president

'You are a convicted criminal!' one man shouted before U.S. Capitol Police removed him from the hearing room.

Texas Democratic Rep. Joaquin Castro asked Abrams if he was aware of the U.S. government transfering any weapons or defense equipment to groups in Venezuela that oppose socialist strongman Nicolás Maduro.

Abrams responded that he was not.

'I ask this question because you have a record of such actions,' Castro said. 'Can we trust your testimony today?'

Engel, expressed concern about Trump's hints that military action was an option in Venezuela, where Maduro is under intense international pressure to step aside and the country's economy is in chaos.

'I do worry about the president's saber rattling, his hints that U.S. military intervention remains an option. I want to make clear to our witnesses and to anyone else watching: U.S. military intervention is not an option,' Engel told a packed hearing room.

Juan Guaido attended a meeting of students in Caracas last Friday with his wife Fabiana Rosales

The head of Venezuela's National Assembly, Juan Guaido, invoked a constitutional provision to assume the presidency three weeks ago, arguing that Maduro's re-election last year was a sham.

Most Western countries, including the United States, have recognized Guaido as Venezuela's legitimate head of state, but Maduro's socialist government retains the backing of Russia and China, as well as control of state institutions including the military.

Under U.S. law, Congress – not the president – must approve foreign military action. At the hearing, Democrats on the committee pressed Abrams on his views on military intervention, but questions about his credibility provoked the most heated exchanges.

Abrams said Washington would keep up pressure on Maduro and his inner circle by 'a variety of means. ... But we will also provide off-ramps to those who will do what is right for the Venezuelan people.'

Panel witnesses described a devastating humanitarian situation.

Steve Olive of the U.S. Agency for International Development said hospitals faced drastically reduced supplies, there were concerns about the power grid and rising reports of malnutrition.

'The situation is deteriorating on a daily basis,' he said.