It was carrying more than 25 tons of dynamite . At least 30 people injured in the incident , government spokesman says . No foul play suspected , spokesman says ; cause under investigation . Of the 140 injured , 30 suffered critical wounds and five were listed in extremely critical condition , said David Aguisn , spokesman for Humberto Moreira , the governor of the state of Coahuila . Mexican news agency reports higher death toll of 31 .
It was carrying more than 25 tons of dynamite . At least 30 people injured in the incident , government spokesman says . No foul play suspected , spokesman says ; cause under investigation . Mexican news agency reports higher death toll of 31 .