Premium Content Subscriber only A Grafton man who made a series of threats against police, including that he had a "hydrogen bomb" during an armed standoff that was livestreamed to social media has been jailed. Joshua Evan Powell appeared in Grafton Local Court on Monday where he was convicted of using an offensive weapon with intent to commit an indictable offence. According to court documents, at about 9.50am on Sunday, September 20 the 29-year-old was inside a shed that separated two homes on Turf St when he became highly agitated and armed himself with a large knife, yelling out threats that he was going to harm himself to family in the nearby property.