Hyderabad, Sept. 10 -- US President Donald Trump on Thursday, September 10, warned Iran that the United States could launch heavy strikes against a suspected underground nuclear site if activity continues there.

Trump was referring to Pickaxe Mountain, a fortified site near Iran's heavily damaged Natanz uranium enrichment facility. The site contains two deeply buried tunnel complexes, while satellite imagery has shown increased construction activity there this year.

"We notice there's a little activity at Pickaxe. I would advise Iran not to get cute because we will have to hit them very hard," Trump said in a speech at a Republican midterm convention in Dallas.

Trump has threatened to strike Pickaxe Mountain since at least July. The fa...