Forty-three people were killed and 20 were injured Friday after a truck crashed into a bus carrying agricultural workers in Mexico's eastern Veracruz state, officials said.
"In total, 43 people died in this accident" near the town of Alamo, Veracruz, on the Gulf of Mexico, government spokeswoman Gina Dominguez told Milenio television.
The bus was traveling from the port of Coatzacoalcos to the northern border state of Coahuila when the crash happened at around 4:30 am (0930 GMT) in the north of Veracruz state.
Dominguez could not say how many people had been on board the bus but she said the rescue operation had ended.
Forensic teams were seen unloading blood-stained bodies at the morgue of Alamo later Friday.
"The first report we have, which we need to confirm with investigators, is that the truck's trailer came loose and hit the bus," Dominguez said.
The truck's driver drove away and the trailer also hit another cargo vehicle, according to Maria Elena, a government worker in the town of Alamo.
The injured were taken to hospitals in the nearby port city of Tuxpan.
President Felipe Calderon gave his condolences in a message posted on his Twitter account.
"My deepest condolences for the families of those who died in the terrible accident this morning in Veracruz," he wrote.
Road accidents are one of the main causes of violent death in Mexico.
Another collision between a passenger bus and a truck on a road in Jalisco state, western Mexico, left 36 hurt and one dead Friday, a state civil protection official told AFP.
The truck involved had been stationary on the Mexico-Morelia road, near Mexico's second city of Guadajalara, at the time of the accident, he added.
On April 5, 14 sugar cane workers died and nine were hurt when the bus they were traveling in crashed into a tree and overturned, also in Jalisco.
Around 24,000 people die from road accidents in Mexico each year, according to insurance companies -- a figure almost double the annual drug violence death toll.
Opposition deputy Arturo Zamora, from the Institutional Revolutionary Party (PRI), told AFP that around 5,000 annual road deaths occurred in collisions with trucks with double trailers, which are only permitted in Mexico.
Many of the trucks traveling in Mexico are overloaded and larger than the size permitted by international norms, he added.