WASHINGTON — The Iranian-backed hackers who stole personal data on Australian lawmakers earlier this year are the same group that attacked the British Parliament in 2017, according to new research by a cyber security firm that sheds light on Iran's campaign of cyber espionage against its adversaries.

A report by Los Angeles-based Resecurity, obtained exclusively by NBC News, says the Feb. 8 hack of the Australian Parliament "is a part of a multi-year cyberespionage campaign" by an Iranian-backed hacking group they call IRIDIUM.

"This actor targets sensitive government, diplomatic, and military resources" in Australia, Canada, New Zealand, the UK and the U.S., the firm says.

Australia has not formally attributed the attack to Iran, but the Iran connection was first reported earlier this month by the Wall Street Journal.

The BBC attributed the 2017 UK parliament attack to Iran, but Resecurity for the first time connected the two events, said Charles Yoo, Resecurity's president.

Using brute force attacks that guessed passwords, the hackers obtained thousands of records from both parliaments containing names, email addresses, birthdates and other information on lawmakers and their staff.

"We don't believe they are really trying to influence elections but we know that they are collecting so-called strategic intelligence," Yoo said.

Resecurity obtained some of the data stolen in the hacks and showed it to NBC News.

In the 2017 U.K. attack, the email accounts of 90 Parliament members were compromised.

The same Iranian-backed group compromised a database belonging to the Liberal Democratic Party of London, Resecurity says.

U.S. officials say Iranian cyber-spying is a growing concern. Earlier this month, federal prosecutors charged former U.S. counterintelligence agent Monica Elfriede Witt with espionage on behalf of Iran. They also charged four Iranians — Behzad Mesri, Mojtaba Masoumpour, Hossein Parvar, and Mohamad Paryar — with allegedly using information she had provided to help them target her former colleagues and conduct other cyberespionage. Witt is believed to be in Iran.

Mesri had previously been charged in 2017 with hacking HBO's computer network, stealing unaired episodes of hit shows and demanding millions in Bitcoin as ransom.