WASHINGTON - U.S. cybersecurity firm CrowdStrike has revised and retracted statements it used to buttress claims of Russian hacking during last year's American presidential election campaign. The shift followed a VOA report that the company misrepresented data published by an influential British think tank.

In December, CrowdStrike said it found evidence that Russians hacked into a Ukrainian artillery app, contributing to heavy losses of howitzers in Ukraine's war with pro-Russian separatists.

VOA reported Tuesday that the International Institute for Strategic Studies (IISS), which publishes an annual reference estimating the strength of world armed forces, disavowed the CrowdStrike report and said it had never been contacted by the company.

Ukraine's Ministry of Defense also has stated that the combat losses and hacking never happened.

Some see overblown allegations

CrowdStrike was first to link hacks of Democratic Party computers to Russian actors last year, but some cybersecurity experts have questioned its evidence. The company has come under fire from some Republicans who say charges of Kremlin meddling in the election are overblown.

FILE - CrowdStrike co-founder and CTO Dmitri Alper FILE - CrowdStrike co-founder and CTO Dmitri Alperovitch speaks during the Reuters Media and Technology Summit in New York, June 11, 2012. FILE - CrowdStrike co-founder and CTO Dmitri Alperovitch speaks during the Reuters Media and Technology Summit in New York, June 11, 2012.

After CrowdStrike released its Ukraine report, company co-founder Dmitri Alperovitch claimed it provided added evidence of Russian election interference. In both hacks, he said, the company found malware used by "Fancy Bear," a group with ties to Russian intelligence agencies.

CrowdStrike's claims of heavy Ukrainian artillery losses were widely circulated in U.S. media.

On Thursday, CrowdStrike walked back key parts of its Ukraine report.

The company removed language that said Ukraine's artillery lost 80 percent of the Soviet-era D-30 howitzers, which used aiming software that purportedly was hacked. Instead, the revised report cites figures of 15 to 20 percent losses in combat operations, attributing the figures to IISS.

The original CrowdStrike report was dated Dec. 22, 2016, and the updated report was dated March 23, 2017.

The company also removed language saying Ukraine's howitzers suffered "the highest percentage of loss of any ... artillery pieces in Ukraine's arsenal."

FILE - Members of a rapid reaction unit of Ukraine FILE - Members of a rapid reaction unit of Ukraine’s National Guard stand in front of howitzers during a ceremony marking the first anniversary of its creation, in the village of Stare, 80 km east of Kyiv, Ukraine, June 2, 2016. FILE - Members of a rapid reaction unit of Ukraine’s National Guard stand in front of howitzers during a ceremony marking the first anniversary of its creation, in the village of Stare, 80 km east of Kyiv, Ukraine, June 2, 2016.

Finally, CrowdStrike deleted a statement saying "deployment of this malware-infected application may have contributed to the high-loss nature of this platform" — meaning the howitzers — and excised a link sourcing its IISS data to a blogger in Russia-occupied Crimea.

In an email, CrowdStrike spokeswoman Ilina Dmitrova said the new estimates of Ukrainian artillery losses resulted from conversations with Henry Boyd, an IISS research associate for defense and military analysis. She declined to say what prompted the contact.

CrowdStrike defends report

"This update does not in any way impact the core premise of the report that the FANCY BEAR threat actor implanted malware into a D-30 targeting application developed by a Ukrainian military officer," Dmitrova wrote.

Reached by VOA, the IISS confirmed providing CrowdStrike with new information about combat losses, but declined to comment on CrowdStrike's hacking assertions.

"We don't think the current version of the [CrowdStrike] report draws conclusions with regard to our data, other than quoting the clarification we provided to them," IISS told VOA.

Hillary Clinton campaign chairman John Podesta spe FILE - Hillary Clinton campaign chairman John Podesta speaks to reporters outside Clinton's home in Washington, Oct. 5, 2016. FILE - Hillary Clinton campaign chairman John Podesta speaks to reporters outside Clinton's home in Washington, Oct. 5, 2016.

Dmitrova noted that the FBI and the U.S. intelligence community have also concluded that Russia was behind the hacks of the Democratic National Committee, Democratic Congressional Campaign Committee and the email account of John Podesta, Hillary Clinton's campaign manager.

The release of embarrassing Democratic emails during last year's U.S. political campaign, and the subsequent finding by intelligence agencies that the hacks were meant to help then-candidate Donald Trump, have led to investigations by the FBI and intelligence committees in both the House and Senate.

Trump and White House officials have denied colluding with Russians.