Yes that's an attack of oppertunity.
We know there was a:
Big fire
Warehouse full of ammonium nitrate.
A missile is superfluous, totally unnecessary.
Catastrophic ammonium nitrate disasters are a lot more common than you think.
No missile was needed for:
Gibbstown, New Jersey, USA January 14, 1916
Faversham, Kent, UK April 2, 1916
Oakdale, Pennsylvania, USA September 15, 1916
Kriewald, Germany July 26, 1921
Oppau, Germany September 21, 1921
Nixon, New Jersey, USA March 1, 1924
Muscle Shoals, Alabama, USA May 3, 1925
Miramas, France August 5, 1940
Tessenderlo, Belgium April 29, 1942
Texas City, Texas, USA April 16, 1947
Brest, France July 28, 1947
Red Sea January 23, 1953
Roseburg, Oregon, USA August 7, 1959
Traskwood, Arkansas December 17, 1960
Oulu, Finland January 9, 1963
Taroom, Queensland, Australia August 30, 1972
Kansas City, Missouri November 29, 1988
Porgera Gold Mine, Papua New Guinea August 2, 1994
Port Neal, Iowa, USA December 13, 1994
Xingping, Shaanxi, China January 6, 1998
Toulouse, France September 21, 2001
Cartagena, Murcia, Spain January 2003
Saint-Romain-en-Jarez, France October 2, 2003
Barracas, Spain March 9, 2004
Mihăileşti, Buzău, Romania May 24, 2004
Ryongchŏn, North Korea April 22, 2004
Monclova, Coahuila, Mexico September 9, 2007
West, Texas, USA April 17, 2013
Wyandra, Queensland, Australia September 5, 2014
Port of Tianjin, China August 12, 2015