NEW YORK (AP) — A former New York stockbroker-turned-Islamic State group militant was convicted Tuesday of becoming a sniper and trainer for the extremist group during its brutal reign in Syria and Iraq.

The trial of Ruslan Maratovich Asainov, a Kazakh-born U.S. citizen, was the latest in a series of cases against people accused of leaving their homelands around the world to join the militants in combat.

“Today’s verdict in an American courtroom is a victory for our system of justice” and against the Islamic State group, Brooklyn-based U.S. Attorney Breon Peace said in a statement. Asainov’s lawyers had no immediate comment.

A onetime broker who doted on his toddler daughter, Asainov converted to Islam around 2009 and later quit his job and started watching radical sermons online, his ex-wife testified. He abruptly left his family in Brooklyn in December 2013 and made his way to Syria as IS stormed to power.

In a case built largely on Asainov’s own words in messaging apps, emails, recorded phone calls and an FBI interview, prosecutors said he fought in numerous battles and built a notable profile in IS by becoming a sniper and later an instructor of nearly 100 other long-range shooters.

“The evidence has shown that people died as a result of the defendant’s conduct. It is time to hold him accountable,” prosecutor Douglas Pravda told a Brooklyn federal court jury in a closing argument.

Asainov, 46, didn’t testify, telling the court he was “not part of this process.”

His lawyers didn’t dispute that he went to Syria and affiliated with the Islamic State group, but they argued that his accounts of his role were boasts that had no firsthand corroboration and didn’t prove anyone died because of his conduct.

“Nobody’s arguing to you that Mr. Asainov’s view of the world is not a very warped view,” defense attorney Sabrina Shroff said in her summation, asking the jury “not to confuse his views with what is needed to convict him beyond a reasonable doubt.”

“There’s not a single piece of paper that ties Mr. Asainov to anything in the Islamic State that would tell you he, in fact, is the person he claims to be,” she said.

Jurors, whose identities were kept confidential, found Asainov guilty of offenses that include providing and attempting to provide material support to what the U.S. designates a foreign terrorist organization. The jury also concluded that his actions caused at least one death, a finding that means he faces the potential of life in prison. His sentencing is set for June 7.

IS fighters seized chunks of Iraq and Syria in 2014, sweeping millions of people into a so-called caliphate ruled according to the group’s iron-fisted interpretation of Islamic law, enforced through massacres, beheadings, sexual slavery and other atrocities. The group’s bloody campaign attracted tens of thousands of foreign fighters; at least scores of them were U.S. citizens, according to a 2018 academic report from George Washington University’s Program on Extremism.

Fighting left a swath of deaths, displacement and destruction in major cities and beyond. The extremists lost the last remnants of their realm in 2019.

Asainov was picked up soon after by U.S.-backed forces and turned over to U.S. authorities. Unabashed as FBI agents questioned him, he gave his occupation as “sniper” and frankly detailed how he’d taught others, explaining that he could spend three hours just on the fine points of pulling a trigger, according to video played at trial.

He had also been forthcoming in messages and calls from Syria to friends and the now-ex-wife he’d left behind, according to trial evidence.

“Have you heard of Islamic State? Right. I-S-I-S. Do you watch news on TV? That’s where I am located. I am one of its fighters,” he told his ex in a voicemail that authorities translated from Russian. “We are the worst terrorist organization in the world that ever existed.”

He sent photos of himself in camouflage garb with a rifle and pictures of the bloodied bodies of men with whom he said he’d fought. He texted one confidante — in fact a U.S. government informant — a rundown of prominent battles in which he said he’d participated and asked for money to buy a night scope for his rifle.

Later, with the sounds of explosions in the background of Asainov’s phone, he asked another friend for money to send his new wife and children to safety as U.S.-backed forces fought to capture the extremists’ de facto capital of Raqqa in 2017.

Shroff urged jurors not to take his remarks at face value.

“To say the same wrong things over and over again does not make them accurate,” she argued.

After his arrest, a defiant Asainov declared at his arraignment that he was an “Islamic State citizen, not a United States citizen,” and jail officials said they later found a hand-drawn version of the militants’ flag in his cell.

He told his mother on the jail’s recorded phones that her son “doesn’t exist anymore,” replaced by a man who saw himself as a holy warrior who fought and killed on divine command, didn’t regret it and would “be fighting until the end.”

“I will never change this path, even if they give me freedom a thousand times,” he told her in one translated call.

“Do you understand?”

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