Iran has announced the arrest of a person who recorded a video last week showing missiles striking the Ukrainian passenger plane that crashed outside of Tehran – but it may be a case of mistaken identity.

The person, who was detained by Iran’s Revolutionary Guards, is expected to face charges related to national security following the military mishap that downed the plane, according to Iranian media reports. Yet the London-based journalist who first posted that person’s footage on Twitter, the BBC says, is claiming that authorities have arrested the wrong individual.

“The person who is a source of the video is SAFE and I can assure you IRGC is orchestrating another lie,” Nariman Gharib tweeted. “They killed 176 passengers on a commercial plane. That’s the real story here.”

The dispute comes as yet another video has surfaced showing Iranian missiles slamming into the plane.

NEW IRAN PLANE CRASH VIDEO SHOWS MOMENT MISSILES HIT AIRCRAFT

New footage from a security camera shows that the airliner was on fire and did not plummet back to earth right away. It attempted to turn back toward the airport, but ultimately exploded and came crashing down out of the sky.

That clip was uploaded to YouTube by an Iranian user around 2 a.m. on Tuesday, according to The New York Times.

Rescue workers inspect the scene where a Ukrainian plane crashed in Shahedshahr, southwest of the capital Tehran, Iran, on Wednesday. (AP)

The plane was headed to Kiev and was shot down just hours after Iran launched a ballistic missile attack on two military bases that house U.S. and coalition troops in Iraq. The attacks were in retaliation for a deadly U.S. drone strike earlier this month that killed Iranian Gen. Qassem Soleimani in Baghdad.

Iran initially blamed a mechanical failure for the plane’s demise before admitting that its own military was responsible. Authorities have said they will "punish" those responsible for shooting down the plane and several people have since been arrested.

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On Wednesday, for the first time, the Associated Press said, an Iranian official acknowledged that claims of a mechanical issue were lies.

“In the last few nights, we’ve had people in the streets of Tehran demonstrating against the fact that they were lied to for a couple of days,” Foreign Minister Mohammad Javad Zarif said.

Fox News’ Nick Givas contributed to this report.