The death toll due to an ammonia spill near the border of Guerrero and Michoacán on the weekend has risen to nine.

The initial number was five but Michoacán Public Security Secretary Israel Patrón Reyes announced Monday that four more victims had died in hospital.

The spill occurred Friday night when a double-tractor-trailer transporting 30,000 liters of ammonia rolled over on the Siglo XXI highway near the Infernillo Dam at La Unión, Guerrero.

The victims were travelling aboard a bus that was forced to stop by the accident and became trapped in a toxic cloud of gas emitted by the tanker.

Among the dead is Eva Montiel García, a nursing student who got off the bus to treat exposed victims, many of whom survived, but she died hours later.

Also dead is a 2-year-old girl who was among several children who were exposed to the toxic chemical.

Patrón said a preliminary investigation indicated that mechanical failure was responsible for the crash.

Some of the victims reported that their insurance refused to cover the costs of treatment, but Michoacán Governor Silvano Aureoles Conejo said his administration is looking into the matter.

Aureoles added that 1,500 people in the community of Infernillo were evacuated to avoid exposure.

The Siglo XXI highway near the accident was reopened to traffic on Sunday.

Source: Milenio (sp)