ROTTERDAM, Netherlands (AP) — Dutch police were continuing investigations Thursday into a threat to a concert venue that prompted the cancellation of a show by an American rock band, as well as into the driver of a Spain-registered van found to contain gas canisters just a few hundred meters (yards) from the venue. Spokesman Gijs van Nimwegen said police would issue an update on the investigation early Thursday. The concert by Los Angeles band Allah-Las in the port city of Rotterdam was called off Wednesday night after Spanish authorities tipped Dutch police about a possible threat to the concert.