Sen. Richard Blumenthal (D) is calling on major airlines to issue refunds for flights canceled last week due to a massive international IT outage.

Blumenthal said he has received reports that airlines have denied refunds to passengers, which he says is illegal. "We're hearing reports that airlines travelers have been denied refunds, which, by law, they are entitled to receive," said Blumenthal. "So I'm calling on the airlines to do the right thing by their passengers: give them the refund they deserve immediately, and automatically, with cash, or rebook them without a fee and provide for the expenses of hotels, alternative transportation, meals."

The Microsoft outage resulted in the cancellation of over 10,000 flights nationwide, according to Blumenthal.