Alex Pretti's horror killing at the hands of US border agents was caught on video by a key witness, who has described the ordeal in a bone-chilling sworn statement. Mr Pretti, 37, was gunned down on the streets of Minneapolis, in Minnesota , by federal agents on Saturday in the second such killing of an American citizen this month. The intensive care nurse was shot several times after a group of armed Immigration and Customs Enforcement (ICE) officers were seen on video wrestling him to the