I believe it's from the 70's and is rock & roll. Perhaps Led Zeppelin. Very commomly played song on FM radio. For rock, it's pretty mild. The only part crystal clear to me is as the music proceeds, it comes to an abrupt stop for a second, then goes into what I can only describe as an "European" siren. By that, I mean not like the old sirens which were a continuous wail and not like the new sirens. This siren is continuous, changing from high pitch to low pitch. High Low High Low High Low. I believe that at the end of the last "Low" a guitar trails off from that point and the song continues it's merry way. I've searched for siren songs 'til I'm blue in the face. Though as I write this I realize what a pathetically sad description I have provided, it's all I can muster at the moment.