The incidents happened since April between the key commercial port of Veracruz and central Mexico.

The state of Veracruz on Mexico's Gulf coast has suffered a wave of violence in recent years as drug cartels seeking to diversify their income streams branch into fuel theft and assaults on trains and trucks.

Shares in the company's Grupo Mexico Transportes unit, which operates Mexico's most extensive rail network, fell almost 2 percent on Friday, while Mexico's benchmark S&P/BMV IPC index <.MXX> dropped 0.75 percent.

Grupo Mexico was forced to close a key route from Veracruz to central Mexico last weekend, after 39 train cars loaded with wheat and four locomotives hurtled down a slope and collided. The railway re-opened on Wednesday.

(Reporting by Noe Torres; Writing by Daina Beth Solomon)

By Noe Torres