A GRANDAD from Ormiston has gone viral after he was recorded hilariously ranting during a prank call.

Retired Kenny Glen was fooled by his granddaughter Rebecca Glen, 18, a former Ross High School pupil.

His fiery response to claims he was a WIFI thief has now been viewed almost 200,000 times on Twitter.

When she set up the prank call, Rebecca who had never heard her grandad swear before was shocked to hear him use the ‘F word’ multiple times.

Warning: Strong language

Rebecca, a part-time cleaner called her grandad using an app.

Kenny heard the voice of a man accusing him of stealing his broadband.

When asked about why he’s stealing, Kenny said: “Who the f*** are you speaking to?

“Who the f*** are you?"

Kenny had no idea his granddaughter was listening and recording the entire thing.

Rebecca said: "He thought it was hilarious.

"I called him afterwards and he said that he doesn't normally answer unknown numbers but strangely decided to do it this time.

"And when I called him he was laughing.

"He thought it was a pal that had set him up but he saw the funny side when I said it was me."

"The funny thing is, I've never heard him swear before so that was a bit of a surprise."

Rebecca shared the hilarious clip on Twitter earlier this week and has been surprised to see it get so much interest.