Iran mistakenly shot down the Ukrainian plane that crashed on Wednesday near Tehran with 176 people on board, US media report.
US officials say they believe the Ukrainian International Airlines Boeing 737-800 was hit by a missile, CBS says.
Ukraine earlier said it was examining whether a missile strike brought down the aircraft – but Iran ruled this out.
The crash came just hours after Iran carried out missile strikes on two airbases housing US forces in Iraq.
CBS News quoting US intelligence said a satellite detected infrared “blips” of two missile launches, followed by another blip of an explosion.
Meanwhile, Newsweek quoted a Pentagon and a senior US intelligence officials, as well as an Iraqi intelligence official as saying they believed the Ukrainian plane was hit by a Russian-made Tor missile.
US President Donald Trump on Thursday said “I have my suspicions” over the plane. “Somebody could have made a mistake,” he said.
Amid tensions heightened by the US killing of top Iranian general Qasem Soleimani on 3 January, Iran has said it will not hand over the recovered black box flight recorders to Boeing, the plane’s manufacturer, or to the US.
Under global aviation rules Iran has the right to lead the investigation, but manufacturers are typically involved.