An Arizona grandmother has said someone subjected her to a so-called police swatting call while she was taking part in a Minecraft fundraiser to raise financial support for her grandson’s cancer treatment medical bills.

The bizarre turn of events is the latest high-profile instance in the US of an act of criminal harassment which involves prank-calling emergency operators to get a heavily armed police response sent to a target’s home.

Sue Jacquot, known online as “GrammaCrackers”, had built a substantial following on YouTube playing the game with her family to help pay for the cancer treatments of her grandson, Jack Self, including playing for 15 days straight.

But on Monday someone falsely called in to authorities that Jacquot, 81, had been shot and killed – and more than a dozen Queen Creek police officers in full tactical gear swarmed the home.

The live stream showed officers entering Jacquot’s room and waking her up. “They just sort of escorted me out, and they were apologizing,” Jacquot told the local news outlet KPNX. “I just wondered what my grandkids had done.”

Jacquot began playing Minecraft as a way to bond with her family. When Jack, 17, was diagnosed with a rare form of sarcoma cancer, his grandmother decided to dedicate all ad revenue from her videos to help cover costs of treatment.

Hundreds of thousands of online gamers took out subscriptions for Jacquot’s channel to watch her, Jack and another grandson, Austin, play the game. A GoFundMe campaign also boosted donations.

However, that also brought the swatting call, which police are now investigating. There was “a call that Jack shot his grandma and killed her – and that he was going to kill himself”, Jack said. “And right then, I was like, ‘Whoa.’ It was kind of like a punch to the stomach.”

Despite the scare, Jacquot says she has no plans to stop gaming. “They’re not going to tell me what I can do. They’re not going to make me afraid to do that.”